Yes, I agree. The reason is straightforward. If one cannot comprehend a drama, how can they determine its quality? Similarly, if a company attempts to market products internationally, inaccurate translations of product instructions could lead to harm or even fatalities. It is unreasonable to anticipate consumer enjoyment or demand for a product/drama if it is not understood.
I primarily rate series low because of the poor English subtitles, which severely diminish the viewing experience. Though I appreciate the storytelling and acting, the language barrier created by the subtitles is a major problem. As a viewer in the USA, I find the subtitle quality especially disappointing, particularly given that these shows originate from other countries. I believe that inadequate subtitles are more detrimental than subpar acting or storylines. I lowered my rating because the show has not addressed the subtitle issues. The lack of attention to this problem will result in a loss of millions of dollars in global revenue.