I can’t say such a book doesn’t exist, but it might take some searching. Anyway, I recommend Cathy Yardley, who writes mainly nerdy characters. Role Playing is a good book with older gamer characters. I’m also really fond of Attachments by Rainbow Rowell.

I don’t remember if it’s specifically nerdy but Small Change by Roan Parrish rates very low on toxic masculinity.

Any subgenres you particulary like or anything else to narrow it down?

Do you want it to only have a male pov? I can think of many books where it has both but just the one makes it much harder.