I'm actually even less invested in Overlord than you. I watched a little bit of it and found it off putting. I was actually far more entertained by the Isekai crossover comedy show where Ainz and Kazuma (from Konosuba) become friends and commiserate over the stresses of leading a cracked team of misfits. While I felt that Overlord was at its worst when it leaned into comedy, the characters actually seemed to work best in that context. That realization made me even more frustrated with the original show.

So rather than wading into the meat of the discussion, I'll make a meta observation:

Taking your characterization of the kinds of comments you were getting, I have a feeling that you're up against a lot of willful "support of current thing" that refuses to consider problems and instead attacks the person asking questions.

It is frustrating when people don't want to engage with a critique and instead choose to categorize you as an outsider or enemy because you want to break it apart for study. But it is also frustrating when someone appears who has only that motivation and isn't interested in enjoying the thing as presented. It is easy to assume that a guy appearing with a critique is just "against the current thing" and wants to kill fun for others as a pastime.

When that tribal instinct to "protect" flares up there's not much you can do to quell it. It is very sad and I've quit many discussions for that reason. Finding people whom you can have good discussions with is, it turns out, much harder than finding topics to discuss. The result is that topic-focused groups can come to resist depth as a matter of pain-avoidance.

There's probably fodder for a conspiracy theory in that where you can assert that media companies are encouraging tribalism around their products for precisely this effect. Smart people who want to move culture forward now have to overcome and navigate that carefully just to avoid being shanked.