Saw one of your posts in a different section and have to admit you are actually a pretty interesting and bright mind. It was about competitive play and improvement, in particular about the common argument that enjoying the game is key to improve.
Thing is though, that the common masses usually do not have that competitive drive to work for their improvement and might quickly give up, if they aren't enjoying themselves enough along the way, hence for most people, enjoying the game is the most important aspect. It isn't actually for improving though, but for not giving up/stopping to play and you will inevitably improve if you keep playing/stick around. Another funny aspect is, if you're having fun, you'll probably be willing to invest more time/play more, which will accelerate improvement.
Enjoying improvement is yet another mindset. Personally I'm of the "playing to learn" mindset, so while I enjoy being competitive/becoming competitive, what I enjoy the most is improving, thus I have the motivation to put in work and actually enjoy grinding.
In short, I agree with your sentiment that enjoying the game is not the best way to improve and that grinding/practicing is very valuable, but most people do not enjoy grinding and would probably stop playing the game quickly. I think in those improvement threads, they should add multiple sections, covering different mindsets and motivations. Would help a lot.