That value is far and away better than Tatum and the Sac pick. The Spur may not be a contender without Kawhi, but they'd've been hosting a playoff series this year with Harris instead of nothing. I like two chances at this draft over a Kings pick which cannot be first-overall and could be as low as 30 if the SAC pick wins the lotto and Philly has the best record in the league. Huge downside, not a huge upside given the potential wait. Obviously, we've had the Tatum debate like a million times already. No reason to keep going there. But Beverly's contract is very good (old-CBA non-guaranteed expiring) and Boban is excellent ballast. When considering what the Celtics will need to use as ballast to make the numbers work, the total value gets even lower.
This completely ignores that LAC would likely offer all that for Kawhi and maybe more, while Boston is probably conservative enough to think the proposed deal is already too much. I could see a Clippers deal getting done quickly and quietly, with Woj reporting it right after the 12th pick is made. A Celtics deal would likely take days to complete, like a lot of stupid news articles going the whole time. Even if Ainge would eventually cave to this deal (which isn't enough in my opinion), he may miss his chance,