I was never called noble, but I did hear things like 'What a good dad you are!' for simply being out and about with my kid. How can they know? FWIW, I've also heard women give each other compliments/praise for the most basic stuff.

I co-parented with my ex, but I still handled a lot of doctor appointments or school meetings. I did not confront other kinds of sexism, that you mentioned, for my involvement in simply being a functional parent. Sorry that happened to you.

I'll just say this for any other guys who might be reading this or going through this now... men aren't as good at maintaining networks social supports... you have to actively seek and maintain them. I had friend groups before marriage and keep them when the marriage ended. Know who your child's best friends are and talk to their parents when you pick kids up from activities. That can lead to playdates and invites to a barbeque. Those things can be a social lifeline for a single dad.