In Retrospect, both REmake2&3 seem like they had to total Budget of one expansive AAA game shared between them and Resistance.
Yeah, this seems very likely.
RE3 in a way feels like the Dark Souls III of RE, in that it's unfair to say it's just reusing assets from Bloodborne because the game wasn't put together in a year, so they're more like shared assets, but because Bloodborne started development earlier, it's clear that these assets were made with it in mind, and Dark Souls III is the one that had to be designed around them.
Applying the same logic to RE, 3 clearly got the short end of the "this is the total budget we have for both games' levels" stick. When it came time to use the available assets to make up for the areas they had to cut, the only ones they could justify becoming a brand new level without feeling like blatant RE2 rehash were the sewers.
And now that I think about it, level variety was also a universal criticism of DMC5. I start to wonder if that's a limitation to their RE Engine pipeline and the resources Capcom has available. I didn't play it yet, but from all the gifs, Monster Hunter World, a MT Framework game, doesn't seem to share the issues. I don't think photorealistic cutscenes (because in gameplay you just see their backs) is worth the trade off, if that's the case.