Mike Brown was unceremoniously fired by the Lakers and Sac. I believe the ends of his Cleveland career came down to LeBron not wanting to play for a coach that was as demanding as he was. Initially the Cavs hired him to rebuild the team after LeBron left and then he suddenly came back.
It is my understanding that both LeBron and Kobe - with some hindsight - acknowledged that Brown was key to their career growth.
I do think that Brown was key to Keegan's development (though the system he ran at the end was hindering him on offense) and there's at least a possibility that Fox liked what Brown was doing - but it also wasn't working. Brown was challenging Fox nightly and Fox often did not respond. That's a bit of a problem if it is also impacting other players down the line and it may have been because the rest of the team appeared to quit.
As it stands I think Brown is a quite competent coach for a team at a certain point in their growth, but he's also a guy that appears to have a style that wears thin after a short time. I would probably give Malone the edge over Brown in 2025 but at the moment each coached the Kings Brown was probably indeed the best coach we have had since Adelman, while also acknowledging that bar is very low to clear. And also while just saying that Adelman was a great coach, the team was over, and it was time for everyone to move on. The issue with the post-Adelman years was the failure to understand that and do a quick rebuild, which spun and spun and spun into 17 years of nothing. It's like when your computer is stuck and you decide to wait out the spinning wheel instead of just reboot. That's what we did. We waited it out. Eventually it ran again, but even then it was slow and probably would have benefited from the reset.
I think this new look Kings will be the same, we might be better than OG Beam Team but probably have a ceiling of 2nd round playoff team, unless you just luck into the right matchup or your playoff opponent suffers an injury mid-series, etc.