I'd argue that not accepting questions from "curated" plugins is bad. Half-bad, at least.
ACF, WooCommerce, Visual Composer, Gravity are extremely popular plugins that a lot of developers would like to have a way to ask / answer questions about.
Crap, I've been through so much pain with Elementor that I could answer most Elementor questions all by myself, yet, it's not allowed and as you can see on their github page (which is slow and doesn't tap into the big community we have), there's quite a lot of developer activity there. Imagine if we could absorb all these people to also post here.
There should be a rule that allows only developer questions regarding to these plugins.
An example of bad questions:
"How do I install Woo?", "How do I set a featured product image?"
An example of good questions:
"Why does WC_Product give an error upon call?", "How to retrieve quantity from a WP_Product object?"
I feel as if these could contribute tremendously to the stack as a whole, given the fact that there's absolutely no developer Q&A-like sites for developers to use in regards to these plugins, usually.
My last and perhaps biggest point:
I'm sure you guys get a lot of off-topic questions in regards to 3rd party plugins, which you delete, so it's not like development questions (that we allegedly now think as "accepted") will not be parsed and rejected if they're simply just support questions, so -
Why not allow them?
Check my discussions / questions for Elementor:
I'm 100% positive that I, as well as many others could've worded these to fit this community and they'd be of great help to anyone that's serious about developing with that 600k active installs plugin.
In response to what others have written:
"We don't allow them because no one cares to answer there, it requires very specific functionality."
I agree and, in fact, my idea of "allowing only some certain plugins" is definitely flawed in the sense of the corruption that it can breed. How do you pick the plugins that you allow questions for? It's a rigged game from the start, though I really believe that for the most popular plugins, which, let's face it, almost everyone uses (Woo, Elementor, VC, Gravity), there's certainly a number of people out there willing to answer, sooner or later.
Though, this is anectodal, of course. I'm basing this off the fact that I know a few WP developers, at different skill levels and that they'd gladly take questions, based on their SE activity on other sub-sites.
So, it might just be worth a shot, given times have changed and to me, WP feels even more vibrant, but definitely more crowded when it comes to low-skill developers.
Just about 5-6 months ago I was a leech 100%. Now I can answer a good chunk of questions pretty easy, I'd take it, with 7-8 more people like me, we could definitely cover some "plugin areas" so it can give a bit of confidence to other developers to try to share their knowledge.