I'm not surprised since I think most UI overhauls replace one system with another that is roughly equally good, except that nobody is familiar with the new system so everyone burns a bunch of time and attention learning the new one just to get back to par. The new UI often isn't worse in any objective sense, it's just not better and the whole exercise is a giant waste of everyone's time.

Some subset of users like re-learning how to do the same basic things in a new way, such as switching browser tabs, but most people want to spend ~0 time on that stuff and get justified annoyed when it's pushed on them.

Of course over time people will get used to the new design, but even if the new one is materially worse what are people going to do? It's not like Apple cares that much about random user opinion and the joy of a monopoly or duopoly is that the companies controlling one don't have all that much incentive to keep people happy.