I would disagree a little bit on the take that Cdrama writers only know how to make viewers suffer because I’ve watched a good amount of Cdramas that had perfectly lovely and acceptable endings, and this is true for historical dramas as well as modern dramas. Maybe the more current stuff has moved in the direction of happy endings - not always as happy as I maybe would want but certainly not unhappy or tragic endings.
There are a number of dramas that have endings that come across as ‘happy’ at first glance but that seem to be missing something. Just because the two actors who play the leads end up together in the end does not mean that they are the actual ‘couple’ we were investing in and rooting for throughout the drama, so it feels a little flat in those scenarios.
There is actually a thread about these types of endings: