Who would need to press the power button to actually turn off or restart the device, right?
The setting to change this is also pretty much buried under Settings -> Special Features -> Gestures.
(Yes, I have no idea why the Assistant is in German when the phone is set to English either 🫠)
The best explanation I saw several years ago: Large tech companies drive change through competing individual teams and projects. So some manager pitched a half-assed idea, somehow convinced upper management to go with it, got developers to heroically implement it, and might have gotten some bonus for doing so. It doesn’t matter if there was no value as long as some decision maker thinks there is (or does not care, or numbers were fudged anyway).
It is literally change for the sake of change.