I don't know that gate keeping is the right word, but I think it's doing a lot in the way of speaking for a number of projects (near infinity) that the author can't possibly represent. I comaintain a piece of infrastructure software that is fairly complicated - it fits the analogue of a commercial building. Setting some arbitrary bar for when to commit would frankly put just a few of us ever working on the project. When newcomers have a thing they want to do we spend a while talking it out in issue comments, then we modify that strategy on the actual PR as needed. To be quite honest, there are parts of this codebase I forget the nuance about all the time, so I'm really only a step or two more familiar than someone that knows the language and can write to the problem they desire to fix at any given time.

Most of my job is reasoning about, "should this feature be in this project" and maintaining some bar for quality in merges. I can always push the latter along if worse comes to worse.