I have to admit I couldn't even understand this problem, because for me the "stock OS" is already unbearable and I'd simply never be able to use it - I've never used it for more than a hour..
But of course I'm talking about non-commercial apps, but commercial app developers would already be on Google Play.
As to relevance to the article - I'm not cheering that much because if Google made "stock OS" even worse then maybe more users would flock to LineageOS/GrapheneOS which would be a great thing and make it harder to push Play Integrity.