I agree that Kingmaker is worth playing. It's a fun game and I actually quite like the kingdom management. It can be awkward early on before you know what you're doing with it, but once you've got your head around it and have a good number of advisor slots filled, it's not really that difficult, though I can totally understand why some people don't really click with it. However, I think that the game would be much lesser were it not for the kingdom management aspect. I love that the game puts as much emphasis as it does on running the kingdom and developing it. The story is unmistakeably about being a ruler, and all the main quests and such revolve around that to some extent. They're almost all things you get involved in specifically because you're a ruler and you have to deal with them to care for your nation. The main quest itself is inextricably tied to the fact that you are in charge and have to deal with the slings and arrows of ruling. I think that without kingdom management as a thing to engage with, it would be too easy to feel like you're less of a ruler and more of an errand runner.

As for comparing WotR with BG3, I think that it's a fair comparison to make, fairer that Solasta and BG3 even, since I think these games are both on the same scale. And I for one am looking forward to WotR way more than BG3. I don't think BG3 is bad, but it definitely appeals to me way less. This is my purely subjective opinion, but looking at them both, there is nothing in BG3 that I think is going to be better than WotR. Even the graphics, while they went in different directions I feel like WotR looks more interesting and engaging overall than BG3. I know it's not entirely fair to judge given how far from release BG3 is, but at this point, while I look forward to full release, I'm not convinced that I'll actually complete it. Where that is not a worry at all for WotR.