Best coach in the league. He's a baby, his offensive philosophy is pretty clearly ahead of the league by about 2 years, and the defensive principles are solid. To my eye, he is actually more willing to experiment in games than Ime was. I think he's a top 5-10 coach right now. Hopefully the ATOs and game management develops over the next year or two.
Remember when everyone, including LeBron, wanted to fire Spoelstra? They said he was too young to be a championship coach. Pat Riley stood by him and the results are clear to see now.
I think you might be on to something. He’s clearly respected by the other coaches in the league, finishing as a finalist for the COTY award.
What a lot of people forget is he's young, he's 34. When Spoelstra was 34 he was an assistant with the Heat. Popovich was an assistant with Kansas. Doc was still playing at age 34, he wasn't even coaching yet, same with Ime. Joe is being judged on a very high bar because this is a high profile job - he took over for a coach that took a team to the Finals and was expected to do the same this season. He's not getting the Will Hardy treatment where he's given time to ease into the job and learn from mistakes and given time to mold the team in his image. He had all of a week to adjustto being the head coach and he's expected to win the championship as a rookie coach. And because the expectations are so high he's judged on that basis - as a coach of one of the league's historically great teams, and he's expected to go better than last season and win a championship. It's that or be fired because we don't want to waste the championship window. I don't think he will be fired if he fails, but people will definitely be calling for him to be fired for wasting a year of the championship window. So he better be close to perfect.
So he's in a really tough position but that's the reality of it. Just as we in real life don't get to choose the problems that come to us, this is the situation that Joe is in and he knew that taking the job. If he didn't want to deal with the pressure and that bar he didn't have to take the job. He will be graded on one criteria - to win a championship. That's the only thing that will be acceptable to fans and media. I'm sure he's not going to make any excuses if he fails, nor will people give him one. It's a results oriented business after all. If coaches like Bud can get fired after winning a championship 2 years ago, and a week after his brother passed away, nobody will make any excuses for poor Joe

Dan Shaughnessy wrote about the pressure Joe is under and got Doc's thoughts on it:
Rivers, who won a championship as boss of the Celtics in 2008, has been an NBA head coach for 24 seasons. He went 41-41 in his first season as head coach in Orlando and did not make the playoffs, then lost a first-round series to the Bucks in his second season. I asked him what was it like to be criticized in his first playoff series.
“I don’t think I’ve ever been criticized,” Rivers joked. “But, listen, we were an eighth seed [in 2001]. So we were the underdog. We were just fighting to stay alive. So that’s a big difference [from what Mazzulla is experiencing]. You go through it all year and then you go through it times 10 in the playoffs. By the time you get to the playoffs, I’d say most guys are ready for it. That’s what you have to do to coach.”
Do you try not to listen?
“You hear everything,” he said. “But you know you put in the preparation, all the work. And you have a lot of coaches. You’ve done what you need to do, so you don’t worry about it much. You worry about what you have to worry about with the players.
“Joe has a lot more pressure than I had in my first year in the playoffs. He’s taken a team that went to the Finals last year. He’s doing a fantastic job. But like me and all coaches, we’re going to be the guy that gets looked at when anything goes wrong. Joe has never experienced that, but that’s just the way it is. But one thing I know about Joe, he knew that when he signed on. I guarantee it.”
Mazzulla was in good spirits before Game 3, even waving off a Celtic PR person who’d declared that the press session was over. Mazzulla was asked to reflect about his meteoric rise from anonymity to a possible spot in the NBA Finals.
“I’m here because of a lot of other people, what they did, what they accomplished and the sacrifice they made,” he said, “and because of what the Celtics have done for me.”
Then he smiled.
Seriously.
https://www.bostonglobe.com/2023/05/05/sports/celtics-coach-joe-mazzulla-has-been-defensive-combative-playoffs/
Personally I think he's done ok all things considered, and I think he's going to be better next season as he learns from his mistakes. But again the ultimate pass-fail of his first season as a coach of the Boston Celtics will be if he can win us a championship. A long fanbase demands nothing less - just ok isn't going to be good enough, fairly or unfairly. Once you take the job nobody cares about how green you are, they care about your results.