«People seem to want simple, predictable, fast and well animated UI»
That may be true, but a lot of sw development is motivated not by what users want, but what programmers think will look good on a portfolio or resume to get a new better job.
That's one of the major pushes for "featuritis" in open source/freedom software projects. Being a "plumber" or "janitor" who maintains a stable application whose author has grown bored with it and who has already reaped the "kudos" for it is not something a lot of people want to invest in; they want to invest in being the authors of new flashy features that look good in their portfolio or resume.