The complaints about Jaylen not concentrating enough on bball / improvement and spending too much time on off-court activities are the same things guys like Shaquille O'Neal went through. Shaq was improving massively year-to-year early in his career as well but he was still getting criticized left and right for doing movies, making a rap album & whatever else he was up to.
This is standard course for young athletes who have publicly visible off-court interests. As far as I am concerned, I am alright so long as I see the player working hard on the floor and very happy if I see improvement during off-seasons to boot. Jaylen clearly meets both of those requirements.
Ultimately, it was only in winning a Championship that stopped those criticisms of Shaq. And even then he still gets a small amount such as (reasonable) claims that he would've won more rings had he worked harder / been more focused on his bball career.
I do think there is some unreasonableness from both sides of the aisle on this one. On one hand, folks are clearly being too hard on Jaylen given his work ethic & improvement.
On the other hand, folks are not being understanding enough to those who are bothered by seeing Jaylen (or any player) not being totally concentrated on bball. Most fans would kill to play the sport they love for a living ... and to be a multi-millionaire several times over. Man, that would be amazing! When they see athletes not working as hard as they imagine they would in the same situation, it hurts them. They get annoyed. When they see the team they love and spend so much time and often money on, and then look at a player who is not as focused on the game as they want to see, they get annoyed. Fans want to see the dedication. If they don't see enough of that and see a player focused on other things, some fans get angsty.
This criticism is hard on Jaylen (and other players) but it is not all unreasonable either.