I also think it's over the top and I'm a year or two shy of being a zoomer. Although, I guess being a millennial is considered old by many now.
I just wish developers would make mobile UIs consistent with the OS. The Apollo Reddit client and, surprisingly, the official GitHub app are the only third-party apps that I have that feel/look like "native" iOS apps.
When it's not over-the-top animations, giant UI elements, tutorial modals, or fullscreen pop-ups, it's small details like the (IMO ugly) custom font and the sharp-cornered buttons in the Dropbox app. At least for that particular app, I can just use the built-in Files app, but no such luck for other apps.