Earlier quoted context omitted.
Ah, sure, it's annoying but it's never giving new permissions you didn't give it before. And yes "revert to default" is probably not what's happening, but reverting to forcing a specific permission grant when the existing one was superceeded or replaced.
Fair, it’s still an example of them not respecting user configuration
I understand the rationale. The app you granted full disk access three months ago might have significantly changed. You can't reset the permissions for a given app after every update, as you might end up prompting the user three times per week.