As far as I'm concerned the problem isn't that one is easier than the other. It's that in the github case it completely routes around the git client. With AGit+gitea or forgejo you can either click your "create pull request" button, or make a pull request right from the git client. One is necessarily going to require more information than the other to reach the destination...

It's like arguing that instead of having salad or fries on the menu with your entree they should only serve fries.