Yeah in that situation, I like to think it really is more efficient and it makes sense to give up preconceptions about etiquette. It seems to me (and I know it's silly) it's fine to use it for more impersonal stuff, but more touchy for scheduling amongst notional peers or people of similar standing, where it sort of automatically signals the requestor is more important than the time picker.

One thing to add, I've actually asked for people to send me a calendly before, I think that's a good social compromise for everyone- it let's me feel like I initiated the transaction, and overall we still get to schedule efficiently.