Adam,
You are right. A part of the problem is there is a bunch (a very small bunch) of people that systematically tries to stagnate progress. For example, some, if they can't adopt have threatened not to update. Other's, clinging to obsolete methods like there is no tomorrow, even when new options are much more intuitive and more flexible. Some don't update in years and expect red carpet service. Some find pleasure digging deep in menus and accept a workaround as a permanent solution. It is unfortunate if such views have impact on development. At times I think they do.

On the bright side, BIAB is amazing and unique software that lets you legally(!) have studio musicians from sitar to spoons and everything in between play on your tracks. If you are using 2024 version, regenerations are about 5-10 times faster than let's say 2023 and prior versions. I thought that would never be possible and it was a huge drawback for me as I do a lot of changes before finalizing, but PGM solved that.
Also, in 2024 MTP Library was introduced. This is non-modal. Meaning, you have full access to all PGM content in one place (Tracks, loops, MIDI, Styles, etc) to use on the fly without having to close window - or use a second monitor. "Bar settings" option which is also one of the most popular tools became non-modal.

Having said that. Content, function and speed are all there.
I believe to make the most of the software as far as Gui/workflow goes in a short run, tools, options and some often used menu items have to be logically combined and integrated into modular and dockable (tabbed) modern panels. Not flashy, but not mid 90s either. Similar as you would expect from music and graphics software. I believe this is very doable and would solve in part both, a lot of unneeded complexity and aesthetics.

Adam, I am curious, what single change to BIAB you think would make biggest overall impact?