Spot on. Based on Flores' "no sacred cows" statement when he was hired I won't be surprised at all if they trade him.
@DMoney has pointed out (accurately) that Tua performed better than both Mayfield and Allen did in their rookie seasons...and probably did so with less help and a traumatic injury to overcome. Not to mention less practice time. Combined with his hype coming out of college, I think all of that adds up to the Dolphins being able to trade him for a better package than what the Cardinals netted by moving on from Rosen.
The Athletic had an article yesterday that mentioned the possibility of Miami moving on after 1 year, and even had a high ranking NFL exec quoted as saying that if Tua was made available there would be teams lining up. It seems possible that Miami could get a late first this year or perhaps something like a 2 and a 4 this year plus a 2 and a 5/6 next year. If the QB market is as hot as many think it will be, Miami will be able to take advantage of that by trading Tua to someone that misses out on the ability to land one of Fields/Wilson.
All that said, I would expect Grier to shop the #3 pick (why wouldn't he?) to see what offers he has for that. Then weigh the cost/benefit of trading back vs. trading Tua and staying put. If someone is willing to sell the farm to move up (like the Falcons did for Jones, the Eagles for Wentz, the Jets for Darnold, etc.), I think I would trade back. That's even while being 99% sure that Tua isn't the guy. For Miami, they are still building and I think having massive draft capital in 2022 and even 2023 could be too hard to pass up.