I don't think anyone really wants to do reverse engineering unless you want to fork out a lot of cash, even then it would be quite a task. Just look at the Allwinner video acceleration campaign for instance.
That said, I'm a bit surprised with the persistance of sticking with -ct since it does seem to cause more issue than it fixes overall(?) as OpenWrt is usually very quick at backing out commits that breaks things. Ben is trying to fix issues but I would be a bit concerned for how long he can keep up since it's a one man band project to my knowledge.
Regard the bugs, realistically I'm not sure how much time they want to spend on troubleshooting a specific device that's been discontinued for more than 2 years (as of writing). I'm sure there are underlying issues but I would guess that they're trying to cover as much ground as possible with as little effort as possible. I'm sure you'd get much more attention if lets say iPhone 8 would crash the firmware as its a much larger userbase. In that regard I'd guess the same goes for mwlwifi, there are edge cases etc and it's overly naive to demand that they should reproduce all scenarios reported.
Worth keeping in mind is that 11ax is starting to pop up so focus is most likely shifting on a corp level as sales > *.