If more of the population were vaccinated the spread of the disease would be curbed (there are still places under 60% vaccination in the US, for example). It would not be sufficient, but yes the point is to create spaces where you have less risk.
The rule is designed to get more people to be vaccinated. It is accomplishing that objective.
(more nuanced is that I don't believe "vaccinated means everything is OK" is the right position either, and that "vaccinate, but also try to do stuff at half capacity" etc etc would be better but...)
A room with 100% vaccinated people is going to be safer than a room with 100% of people showing up with day-old negative covid tests. (EDIT: actually not sure of this as much now that I'm thinking about it...)
Ultimately the rules forcing vaccination are a result of a huge part of the population refusing vaccination, which is the single most effective policy. It's roundabout because governments don't have the courage to just force the issue (or waited too long and now there's a coalesced movement against it).
Sorry if unvaccinated people feel bad because of it. If they cared about not getting people sick they would vaccinate. Taking covid tests every day doesn't improve your immunity.
