Well, I want a phone that's about one tier below flagship and has certain features. I don't think that's unreasonable.

For comparison: The feature I look for the most is a microsd slot. The last time that option existed that was in the quality range I want, I bought it. For anyone buying a phone right now, samsung has dropped microsd support from multiple more tiers, google and apple have never offered it, motorola and some others have the physical hardware but won't properly update the phone...

That's a feature that has been demonstrated to have no meaningful downsides, and manufacturers won't put it in to good models. I'm not convinced batteries are very different. People's refusal to make huge unnecessary compromises doesn't prove any features are DOA. I can guarantee that the above phone using LCD instead of OLED isn't a compromise for the battery's sake.

The biggest downside of removable batteries is that it's not an option on good phones. There might be some solid physics-based reasons, unlike with microsd, but I'm skeptical.