Kingmaker was able to capture the feel for whatever reason
Not really. Kingmaker's game feel is about as far from IE as PoE was, just in other ways.
I agree. For me the main culprit was the amount of magical items you get.
Itemization doesn't have anything to do with game feel
The point Nihilste raises is about how the game handles in your hands, and his point is that PoE didn't capture that RTS-like feeling of fast management and "micro" in the traditional Starcraft-sense of the word, which I agree with. I just don't agree that Kingmaker captures it either. I like both games (though Kingmaker got old faster and I don't think I'll replay it as much), but both have systems that punish movement severely and deliberately make movement sluggish to avoid the insane kiting shennanigans etc. of the IE-games. The price they pay for this expansion of tactical depth is the IE-game's focus on constant movement and kiting-micro. But chiefly, what people mean but can't explain when they say PoE or Kingmaker don't feel like Baldur's Gate is the fact that movement is deliberately sluggish, penalized and as a result combat feels more unwieldly, though you do obviously also gain some benefits i.e. you have to think about how and when to move.
I think I've come to agree with
Sensuki on some of these points over time. That is, the primary benefit of real time is the focus on movement and micro, simultaneously avoiding threats while keeping your guys grouped up enough for buff, cleansing, healing or whatever if necessary. If you're gonna make it about having trade-offs to movement, turn-based simply seems like the obvious choice, and I'm fairly certain PoE would have been much better as a turn-based game. Same goes for Kingmaker.