Put it this way, maybe this will help some people out.
Patriots get: Trey Hendrickson (who is currently injured, by the way) +~10 million in salary the rest of the season. He is a free agent after the season. You're getting him for, best-case scenario, 12 games, assuming he misses no time. Realistically, assuming he plays well, that's what, 8, 9 sacks? Average run defender.
Bengals get: Keion White, who has been pretty bad, but is still developing, cheap, and will be allowed to do whatever he wants on that defense, and is under contract for two more years. You're also getting a pick likely in the top-125 next season.
So you're making the Bengals better long-term, getting them out of cap hell, and giving them two young, cheap players.
In return, you're getting a 2nd-tier pass rusher for a little more than half a season, and hamstringing your cap this year and next year, since his contract involves a void year for 2026, a 6.5 million dead cap hit. And you're losing Keion White. Who comes in if/when Hendrickson has to miss a couple of games?
It's way too much to give up for a team that's still building a program.