Only for server-supplied timestamps.

Like the time clock example: sure what you're describing works if the user is just pressing a button to clock in and the server stores a UTC timestamp in response to a POST request or whatever.

But it's very common to need to backfill time. So the user backfills with their own supplied timestamps, those stamps get converted to UTC, tzdata changes a few months later, and HR is now asking for an explanation as to why they were late for those backfills and how it's possible they were working an hour after the shop closed.

It's never as simple as "just store it in UTC".

Conversion to UTC is lossy, so I prefer to keep up with the user-supplied time where appropriate.