I too have the impression the idea of "Kaizen" firmware updates has been abandoned. For example it would be nice if the existing X-Trans IV cameras would be updated with the latest JPG features and fim simulations, they all use the same sensor and same processing unit after all. The X-T3 in particular, but the X100V and X-Pro3 are also missing Eterna Bleach Bypass. It's even more obvious, because recently released X-T30 II has all the latest stuff, while the original X-T30 gets nothing.
Another feature I'd like to see is the ability to disable certain film simulations, so they aren't shown anymore. The list of simulations is getting longer, there are some however I pretty much never use, like Velvia, Monochrome or Povia. Being able to make those invisible and only making them visible if I really want them, would be nice.