Mask guidance here has recently changed - after a little more than a month of being told "if you're vaccinated you don't need to wear a mask" we're now being told we should be wearing masks when indoors again, vaccinated or not.
Tbf, I think I hadn't seen a mask around anywhere for a month and statistically it's unlikely that everyone I was seeing outside was actually fully vaccinated (and that's a problem with relying on the "honour system" with matters of public health tbh)... but now that the delta seems to be spreading rapidly and vaccinated people are a powerful transmission vehicle (because most vaccinated people either show no symptoms or very mild symptoms).