I can't remember the last time I talked to a gay man who wasn't on PrEP. It's arguable that in reasonably responsible circles, HIV these days poses little-to-no risk, even among sexually promiscuous people. And most other common STDs are completely curable. The big exception is herpes, the spread of which is not prevented by condoms.
If a sore is outside of the area covered by a condom, a condom doesn't do anything. But I am reading that it is recommended to use condoms to prevent the spread of herpes generally, even without an outbreak.
I don't have the source to share, but I read that some types of STDs are more and more resistant to antibiotics, to the extent that they need combinations of multiple, last-instance antibiotics to cure it.
