What would work IMO is someone with money paying the developers and the designer but force them do do customer support, you don't play with the new shit until most tickets are resolved and customers waiting for response are satisfied. maybe a paid support would help too.
Market success has almost nothing to do with product quality. Well, okay, it does, but only in the sense that you need to not actually be a total fraud. You can get away with dismal quality as long as your marketing is good [1]. In formal terms, software development is a loser's game [2].
[1]: https://danluu.com/nothing-works/
[2]: https://news.ycombinator.com/item?id=26660679
This implies that the churn you're complaining about has nothing to do with market success. You might not like it, but that doesn't mean the failure of Linux on the desktop is actually caused by it.
The Titanic didn't sink because of the arrangement of deck chairs, and Mozilla didn't sink because of any features they did or didn't provide (and GNOME didn't fail to achieve significant market share in the first place because of features either). The actual problem doesn't have anything to do with the stuff on the deck at all.
It's the one-two combination of vendor-lock in and bottomless marketing budgets. Since most of the value of the Windows platform and the Web is the immense amount of stuff that's built on top of it, there's a huge lock-in effect that prevents you from even reaching parity, much less exceeding it. And in order to overcome the marketing budget and pure inertia, you need to be ten times better, not just on par.
If GNOME becomes as usable as Windows, it won't have anything to do with what they actually do in the desktop environment itself one way or the other, whether it's continuing on the road they take now, or reverting everything back to the way GNOME 2 was, it's totally irrelevant. GNOME becoming usable will be entirely because of Valve investing in Wine, combined with a whole bunch of other apps moving to Electron and shipping Linux versions because heck why not?
Unfortunately, while they are probably already on par with Windows, they aren't ten times better than the Mac:
* The Mac has a bottomless marketing budget. Good luck competing with that, GNOME.
* They've shown a lot more restraint than Microsoft has, probably because macOS is considered a niche product to round out their catalog rather than being their one and only operating system like Windows is for Microsoft. They have even reversed course on a few anti-features, like adding back USB-A ports to the Macbook Pro even though it made the laptop slightly thicker. And unlike Windows RT, they didn't lock down the ARM Macs.
* Those tectonic shifts I mentioned that made Linux usable? They also make the Mac usable, because Wine is open source and Electron is basically its own operating system. Anything truly good that GNOME does, Apple can copy it just like Chrome copied all the really good stuff from Firefox.