It's a pity.
Look at the school everyone was talking about yesterday. In an unvaccinated population of adult-sized teens, the risks of transmission are still quite high, and in terms of virus drift/shift, it's an environment which the most tramsmissible forms.
I think indoors groups, for all those who have reached adult size (so secondaries) where distancing in not possible, should remain mitigated by masks. I would take a different view if:
a) teens could be spread out, as aduits are for other indoor groups. Not possible in classrooms
b) this was about something optional (like going to a club, bar, theatre, cinema) so those who have specific vulnerabilities can choose not to attend and not miss anything crucial.