It bothers me that people always give BL dramas high ratings when in reality most of them are very bad, and they do it just because they are BL. I feel that by doing so, they are undermining the credibility of mdl ratings, and that makes me distrust the ratings on this website. I think people do it because they believe that this will lead to more BL dramas being made, but they don't see that by doing this, they are encouraging directors to make crappy dramas, because no matter what they do, if it's BL, it's going to get a high rating. And that's why the quality of BL dramas is so low. 

I wouldn't dare to compare ratings for het romance with ratings for gay romance, as I haven't watched a pure het romance for ages. 

But I do notice that dramas, regardless of genre, are subjective to misleading ratings.
Sometimes due to fan wars, whether mass upvoting or mass downvoting. Sometimes just because -- for example, Japanese titles generally are reated a few points below Korean titles.

 Roxanne_aishi:
when in reality most of them are very bad

I'd be interested to hear which BLs you've watched to come to this conclusion.
I took a look at your watchlist and couldn't find any in either your Completed, your Dropped or your On-Hold lists. On your Plan to Watch I found exactly two BLs (My Love Miy-Up (Japan) and Ossan's Love Returns) and one Chinese censored BL (Winter Begonia). I might have overlooked a few. (Yes, I scrolled through all 2358 items on your PTW list.) 

I would say there are quite a few BLs of dubious quality, and there are many more mediocre ones, as well as a few outstanding BL dramas.
But really, I can't imagine that it's much different with het romance dramas. (Or GLs. But their sample size would still be too small to make a reliable statement.)
Any kind of "quality" distribution usually follows a Gaussian Curve.

 Roxanne_aishi:
no matter what they do, if it's BL, it's going to get a high rating

Not true. There are BLs with a rating of below 7.

 Roxanne_aishi:
And that's why the quality of BL dramas is so low

If we're talking about quality, we should consider that live-action BLs still are a niche product, with a very specific kind of target audience.
a) It has been hard for producers to get funding, Still is, in most countries, epecially in South Korea, except in Thailand, and they have a different kind of problem, with one company dominating the market.
b) Until very recently, viewers have been happy to get live-action BLs at all, let alone high-quality ones. Only in the last two years or so, have we seen an rise in numbers equalling the Cambrian Explosion.
c) Audience demographics skew towards younger viewers who can be easily excited.
d) And with teenaged girls as the target audience, topics in BLs  have tended to favour easily digestible school romance. As I said, we are in the midst of something similar to the Cambrian Explosion, so we are currently seeing a diversification of genres and settings.
d) Sex sells.

 Roxanne_aishi:
in reality most of them are very bad

This is your opinion. So what, we all like different things. Like everything else, quality varies. There are some real clunkers but others with excellent story-telling which hold their own against their het counterparts. Even with their lower budgets and shorter run times in most of MDL's countries.

 Roxanne_aishi:
they do it just because they are BL

They do it because they get what they're looking for. Just like everyone else, you included. And I say this as someone who likes coming of age, youth series and certain qualities in story-telling and isn't fussed what orientation the protagonists are - which means I'm looking for different things than a lot of BL viewers. Their ratings are little use to me. So what? It reflects their preferences.

 Roxanne_aishi:
that makes me distrust the ratings on this website

For ALL dramas? Seriously?

The different fan bases tend to rate differently. It's something to be taken into account for every genre and country.

Use the filters to X out gay romance if you don't want to see it in search. There's one very active thread and the games thing skews BL, but it's nothing compared to the promotions for het K-drama and K-celeb news on the site. If it doesn't suit you, just ignore it.

 Roxanne_aishi:
they are encouraging directors to make crappy dramas

Those involved in those decisions will pay far more attention to viewing numbers than MDL ratings. We're not that important. And yes, the ratings will encourage some to start and there will be a percentage of those who complete because they can't stand to drop, but it's a small drop in the total number of viewers.

 Roxanne_aishi:
the quality of BL dramas is so low

There's currently a glut of BL because it's popular, some are being churned out because of that. There are plenty of mediocre het dramas too, like the spate of K-drama riding the wave of US interest.

Please be careful about allowing your biases and limited data set to condemn an entire genre because you haven't seen any you care for. There are lousy BL and excellent BL, just like het. If you are open to watching some and find it hard to choose, ask someone who watches BL and likes the same things you do in het series to suggest some BL with those particular qualities.

I think it's because these days people make BL dramas just for profit without minding the quality. The actors are newcomers who can't act, the plot has messy plot or no plot at all. But not all BL dramas are like that. For example; Khemjira is really good so far. And I heard Shine and My Magic Propechy are also really good (just not my taste).

My colleague stop watching BL dramas for months because she lose hope on BL plot, BL industry, and BL actors. Except for Bilkinn-PP Krit. I told her to watch The Red Envelope (LGBTQIA+ movie) and she watched it.

For the rating, I think people have lower expectation towards BL drama, including me. I think I once rated a vertical BL drama 10 (my bad). But it happens with K-dramas too, people have lower expectation towards K-dramas. That's why I usually won't watch a K-drama receiving less than 8.6 rating, because K-dramas are usually overrated.

Honestly, Red Envelope was great, as was Marry My Dead Body (still upset that GG Precinct was a side story rather than a sequel but eh. Entertaining enough at the time).

My experience might be a bit skewed, as I don't tend to watch romance dramas much.  Generally, when I do, I tend to gravitate more towards BLs as I tend to prefer the character interactions (not always obv). Censored adaptations from China like Winter Begonia, Justice in the Dark, The Spirealm, The Untamed etc, are incredible in terms of quality storytelling and acting, interesting storyline and re-watchability. Comparing, say, Winter Begonia to Story of Yanxi Palace (two of the directors worked on both projects)- you're definitely looking at a high-quality production in WB (if you're ok with censored adaptations).

Thai BL dramas get a lot of flak for being bad, but there are some complete gems. Khemjira is great so far, Ones like To Sir, With Love, Not Me and 100 Degree Longitude Passes Through Us (and likely a fair few others that slip my mind as it's 5am here and I just woke up) are definitely high quality. Sure, there's a lot of milling of the genre, but you'll get that with straight/ het dramas (romcoms especially)

Can't say much, though, as I tend to be pretty fussy when it comes to romance, but certainly no shortage of quality BLs/ censored Chinese adaptations. It can take some digging, however.

(Unpopular opinion, maybe, but I can't really get into k-BLs...I feel I might be going to MDL jail for admitting that lol)