You? The other maintainer didn't ask you to do that. You're not entitled to even a minute of another person's time just because you unilaterally decided to dedicate hours of yours on something.
> I rarely even send PRs these days because those often rot for months or years.
Mind you, I've rarely sent PRs, but when I do, I do it with the intention to help. Only around half of the PRs I've ever sent were merged, and most of the others were left open without review. You know what I think about them? Nothing, I just conclude that the maintainer is probably too busy or my proposed changes are not within the goals of the project. I then move on and don't let it eat at me.
> let's be great to one another.
I think that includes giving other maintainers the benefit of the doubt. That includes not taking being ignored as a personal insult, I think.