re: Zion, Poole and Murray will make a combined $108.9m next season

I wouldn't say you gain nothing.

Let's say just for shits and giggles, b/c this won't happen, but let's say we traded Zion and Poole in February and got back mostly expiring contracts.
That's $76M gone, plus another $8M from Looney who isn't returning next year, so $84M off the books for next year.

We'd be at $110M in salaries with 11 players. Expected cap is $166M. Let's just assume we have another $30M in salaries on guys we took back in trades, leaving us with $26M in cap space.
Even if it was less than that, say $15M in cap space, what you can do with that is bail out a team that's deep in the tax, like the Bucks or Cavs or Wolves.
A trade of $7M Hawkins for $23M Naz Reid is now legal, and it gets them comfortably out of the tax and allows them to use some of the MLE. They can't afford to be a tax team for the 3rd consecutive year, next year.


The Celtics traded $30M Porzingis and a second for $8M Niang and $15M Mann, saving them $7M. The Jazz then absorbed Niangs contract from the Celtics for 2 2nd round picks. The Nets absorbed Mann's contract for the #25 pick in the 2025 draft.
Celtics spent 3 2nds and a 1st to get rid of $30M.


So it can be beneficial, especially when rebuilding, to have some cap space to make uneven trades or absorb salaries from tax teams needing to shed salaries.