I'm not saying Ainge wouldn't do this, but this is just a blogger's proposal. It should not be labeled as a "rumor."
I would be concerned Beal would just be a repeat of Kyrie, not chemistry-wise but in terms of Beal leaving for nothing in a couple years. If they dealt for Beal they would still need to make more moves to become a contender - if that move doesn't happen, what's to stop Beal from joining some other superteam in a bigger market?
A couple years ago, targeting Davis was a realistic goal since we had the most assets and it was evident New Orleans was going nowhere. Now we don't necessarily have the most assets and Giannis is in a good situation in Milwaukee. I'm not as confident we can make a superstar deal after any theoretical Beal deal before his deal is up, as all the really good PF/C's are tied up.
Anyway, I understand you have to take risks sometimes but Jaylen Brown is more valuable than giving up damaged goods Thomas and a 9th overall pick (at the time, the Celts estimated BKN's pick would end up around 8th overall so they valued it correctly). We could always re-sign Brown and he'd still be a trade asset in the future.