I got my second dose of Moderna on April 8. At the time the CDC recommendations said you normally didn't have to wear a mask if you were fully vaccinated. I was thrilled. But, shortly thereafter, I read the paper at
https://www.cdc.gov/mmwr/volumes/70/wr/mm7017e2.htm and decided to go back to wearing a mask when I went to the store, etc. I did it out of an abundance of caution to protect other people and to do my part in lowering risk of community spread.
This is why: The study described at the link is, I think, a very good one. It was in a relatively controlled situation where they could routinely test everybody. They were able to identify asymptomatic cases because they were testing care facility residents daily as well as testing health care staff twice per week. The study is also interesting because the variant involved, though not one that made the news, had multiple spike protein mutations.
You can see results by clicking on the "Table" link to the right. Unvaccinated people were twice as likely to get infected as fully vaccinated people were. But the big difference was that, if vaccinated people DID get infected, they were much more likely to be asymptomatic. 14 of 22 infections among vaccinated were asymptomatic vs. just 2 of 22 infections among the unvaccinated. That is a highly "significant" difference in terms of statistical significance (>0,99% confidence). It also means that, while vaccinated people in the study were less likely to be infected, they were MORE likely to be asymptomatic infections (91% confidence). 14 of the 16 asymptomatic infections among people in that study were vaccinated people.
That made me decide to start wearing a mask again. The CDC was saying, at the time, that even if you were infected you were much less likely to transmit due to lower viral load. But when I (for example) went to a store I did not mind the VERY minor inconvenience of putting on a mask in order to lower the risk to the poor people who have to be in that store for hours interacting with people they don't know anything about.
That's not "virtue signaling." That's acting responsibly in consideration of other people.