That isn’t exactly true. If I charged $1,000,000 to be in my book club, that would certainly be a high barrier to entry, but it doesn’t mean I’d get better readers/insights/conversation.
I’ve had PRs merged. It’s doable, yes. But there are many custom_components that I use where the project developers simply refuse to submit it to the main code base because getting it there is just too much effort.
If the code itself isn’t up to par, the PR can always be rejected. I doubt the HASS project is INTENTIONALLY difficult to get started with in order to weed out bad developers. That’s just the way it has worked out over time.
It’s not really higher standards for entry (though HASS has those too), it’s just a higher barrier. It’s a hurdle that doesn’t HAVE to be there, it’s just developed that way and would take more effort than anyone is willing to put in to undo it.
I can’t imagine anyone arguing AGAINST a flexible plugin system that allows for on the fly upgrades, reloadable everything, and all core features available to the plugins. The worst thing that will happen is someone makes a crappy plugin that breaks things and people stop using it or it gets removed from the “store”, and that’s already possible with the custom_component system.