Would this be wrong?
I like talking to random people. I can spout a lot of info at them, if they are receptive.
If nothing else, some of these people need a little nudge.
I have been bringing up these issues to people I have met, but not by me approaching and saying things like this. I have been surprised at how many agree with me, even though most of them really don't have any facts. They just see that something ain't right.
Just talk to them as you would to anyone, try to be engaging and occasionally say "What?" so they have to repeat, eventually say "it's really hard to understand people through a mask." That's a fact no one can argue and isn't personal to them. If they take up that line keep it impersonal! Talk about the loneliness and disruption caused by "mitigation" measures. You don't know what's going on with strangers. Much more likely that you harden their attitude by attacking their choice, than that you change their mind. The best you can do is make them think about the negative consequences of masks.