I was thinking about the Tua and Dolphins thing some more.
Put it this way. Tua is worse than these 6 AFC QB's and probably will be the entirety of his career: Mahomes, Allen, Burrow, Jackson, Herbert, and Lawrence. Next year, he will almost certainly be worse than Watson (though this year you might take Tua). It is arguable that if you needed to win one game on who you'd rather have between Tua, Tannehill, and Carr (obviously Tua's age makes him a better long term choice than Tannehill or Carr, but in a vacuum you could say those guys are better than Tua or it is at least arguable). That says nothing about Wilson who perhaps will rebound (or maybe he is just done). Bryce Young and/or CJ Stroud may end up in the AFC next year.
Given that, the Dolphins cannot sign Tua to a massive long term extension. He will never be good enough to earn it. Now if they can sign him at 25 or 30 million a year, they can probably get by with that, but if Tua wants anything close to "market value", then they have to move on from him as he just isn't good enough and never will be. He is too small, too injury prone, not athletic enough, and can't throw the ball well (or deep) enough, to hitch your wagons to long term with a big money contract.