Vaccination is variolating: it lessens the impact of the infection, not preventing the infection, and thus the potential to be contagious.

A vaccinated person who has been infected is still contagious, just less so than an unvaccinated person.

Think it's still preferable just because vaccinated people can still catch and potentially spread it, and the risk of exposure is still pretty high due to all the people not vaccinated.

Most places don require masks at all. The recommendation (for now) is to keep wearing mask as before.

I assume this will change as/if/when more people become vaccinated.

Mask rules will change as active cases fall. There is a 10-30% of the population that refuse vaccines for political reasons. All we can hope for is everyone else getting the vaccine, and most of the anti-science people getting immunities via an infection.