Is that how all these third party iOS apps all have completely consistent “pop” animations on long press?
On-topic: they should build an M1 app that simulates loud coil whine at low-CPU usage, so you can feel like you're using a Dell XPS.
I'm using a tiling window manager with mostly GTK apps, so pretty much all menus and such look the same. The worst offenders are Firefox and IntelliJ, although they have improved a bit lately.
However, I'm not sure that this is the reason for lack of adoption. Windows has always been a patchwork of interface design, every other app having their own special window decorations and behavior, including MS' own apps (thinking of Office in particular). Also, seemingly similar elements, such as text inputs, behave differently in different places. For example ctrl-backspace sometimes deletes the previous word, sometimes it introduces random characters.
Basically, it's like an iframe — you declare what contents this portion of screen should have, and the render server composes it onto the screen. The render server is shared between all apps (just like in X11), so it can compose different apps with dependent effects (like blur). Apps don't have direct access to the render server's context, just like a webpage doesn't have any way to extract data from a foreign iframe.
The scrolling animation is 99.9% of the time implemented as a client-side animation timer submitting non-animated hierarchy updates to the server. It’s common to have janky scrolling.