I've written a couple times on Medium about how I (as a gay man) get random dick pics from strangers too, and about how I hate it. I'm not talking about on Grindr or something where such behavior might be more expected if not exactly joyously received.
I mean on Facebook Messenger and Twitter and public platforms like that, which I use professionally and not to socialize or find guys to date.
For some reason, a small subset of men feel entitled to send out pictures of their erect penises. They don't seem to understand that I don't want to look at that with my coffee in the morning. Some guys have even asked me after I objected, "Aren't you gay?"
The implication is that because I'm sexually attracted to men I'm interested in every man's engorged genitalia. Talk about entitled!
This is the kind of mindset that helps me understand what women are talking about when they say they feel threatened by men very frequently.
I can't imagine what it's like to not recognize boundaries like that, but I get these sort of photos often enough to show me that men without such boundaries exist in large numbers. Big problem, especially for women.