what the fuck do you think timezones currently do?

Are they just arbitrarily stuck to "maybe sometime close to local solar time"

It could literally be equally as granular as existing timezones. You could just remap timezones to the offsets directly, hell even less granular because who cares. Just delete the half hour offsets.

it's not adding anything new, that's not the point, in fact it's impossible to add something "new" to the concept of time, we've already defined it. It's an improved variant of timezones, where coordination is immediately more accessible, and less involved. It's explicitly less arbitrarily defined than the current timezones that we have no, because most of the time, you just wouldn't use them.