I'd rather have an imperfect frame now than a perfect frame later. Latency should be the top priority for any UI, because when latency is low enough it feels like a part of your own body, which minimizes cognitive load. Animation is especially bad for this, because animations add hundreds of milliseconds of latency.
You might have thought the title was about Wayland and you're right. But this isn't about Wayland.
I think that's a false dichotomy. The examples the author gives would not be slower in any way if done correctly.