So, my feelings on the trade are well known. Terrible value, we should have kept JB and mended fences, or paid the price for Giannis. It was unacceptable to end up with a 36 year old with a history of physical and mental health injuries. We've taken a giant step back in terms of being able to win a title, and there's no clear avenue to get back to contention.
But, I do think that parting ways with JB probably goes beyond analytics, his relationship with JT, his contract, etc. My guess is that management / ownership had some concerns about an outspoken player without much of a filter who was also prone to conspiracy theories. JB thrived on feeling aggrieved. It fueled him. But, one false step and it can turn into a PR nightmare.
This off-season, JB immediately went on Twitch talking about this being his favorite season. That rubbed people the wrong way, because it seemed to be a comment about personal achievement rather than team success. He also vocally picked a fight with the Beverly Hills PD about them shutting down an event he was hoasting.
In the past, he's had controversies with the Olympics selection committee and has been associated with toxic personalities like Kanye West and Kyrie Irving. He kept up a social media post applauding an anti-Semitic group outside of MSG, even after being educated about the group's offensive views.
And, his social media platform seemed to be growing. My guess is that one of the reasons the team didn't want to keep JB on board is because they saw him as a ticking timebomb, somebody who would eventually say something negative about the organization or something so toxic that it reflected poorly on the team. The Celtics try to keep a very clean team image (remember Ime), and I can't help but think that this factored in.
Players rightfully hate the phrase "shut up and dribble". They're citizens, too, and they have a right to speak their minds. But, it's also a business, and no business wants a high-profile employee that might create a media firestorm.
That's the only way the trade makes sense to me, i guess. The team worried that JB would do something to damage the brand. (Although, how much can words actually damage the brand? The league is full of guys accused or convicted of domestic violence, there's a gambling scandal, etc. Kyrie is back to being celebrated again. I would imagine anything that JB said would blow over without any real damage.)