My guess is typical mask wearing might be fairly effective for short exposures, but less so for longer exposures, like longer journeys on public transport or being in a shared office for hours. Things like ventilation would also be a factor.
As far as the UK goes, we're not relying on masks at all anyway. Mask mandate on public transport, shops, etc., ends next week, the mask wearing we briefly reintroduced (and I mean briefly, it's only been in place for a couple of weeks) for secondary schools is being lifted from tomorrow.
We're also planning to end compulsory self-isolation entirely from 24th March, and that might be brought forward.
Basically betting that vaccination is sufficient to keep cases and severe impact at a tolerable level. Tolerable for who is another question.