I was going to reply to @fake-married-my-dead-fiance comment about My Royal Nemesis, and the plot suffering from compresesion. But then the reply turned into a long ass paragraph so I'm just dropping it here instead!
I've had time to think about the drama now that I'm sufficiently removed from the sheer euphoria of having an actual good kdrama to watch. And I think so much of why I liked MRN has to do with the fact that in times of kdrama drought, this was something original. It didn't follow the bland cookie cutter route of modern Netflix kdramas. Or even the tired and tested green carpet discourse that broadcast kdramas have turned into post Lovely Runner (I don't entirely blame that drama for it but man it did start a trend of loser boyfriend as ml that I've since come to dispise).
MRN was something fresh that leaned into the roots of earlier, nostalgic kdramas. It found a middle ground between toxic chaebol mls of yester-year and the green flag down-bad loserism of today. Coupled with the fact that the leads looked and felt more mature and gave such nuanced performances, it easily became the next best thing in kdramaland now. But it is a flawed project, that left so many questions unanswered. The writing was nowhere near the nuanced sheer perfection and storytelling of older kdramas that didn't shy away from creating deeply flawed, unlikeable, morally grey protagonists. It's nowhere close to that additive feeling and the watchability of older dramas. MRN was good, but more so in comparison to modern bland kdramas saturating the market currently.
So yeah, while the episode count was certainly a problem, it was the least of it. At the end of the day, kdramas have become too "safe" and sanitized. In an effort to adhere to "woke" principles (mainly the flag discourse, thought pieces on twitter/reddit), too afraid to offend any demographic, and in trying to cater to all audiences, they have basically left themselves little space to maneuver when it comes to storytelling. The result is the formulaic, vanilla dramas we see today. MRN was an outlier in that it dared to look back and bring in the elements of og kdramas that made us fall in love with the genre in the first place! So, while I'm not 100% satisfied with the ending, I do hope the sheer popularity of the drama inspires writers to look beyond the formula and dare to write things that are a tad less beige or verdant.