It is truly weird to me that the standard workflow for submitting a change to someone's project is now to make a copy of their project, change it, and then ask

It is truly weird to me that the standard workflow for submitting a change to someone's project is now to make a copy of their project, change it, and then ask them to import your change. This is inside-out and upside-down! Surely it would be a million times more intuitive for forges to offer a "submit a patch to this project" feature?