I think Rojas is the next Bryson Stott. If he's not quite ready, he'll go back down and come back up. Williams actually spent forever in AAA, was not rushed at all. Brown got pressed into service after a Vic injury but if anything was not used enough (and got jerked around in terms of both role and position) once he came back up for good. Kingery is the only one who should have gone back to AAA but didn't due to a combination of his contract and injuries.
Stott was not especially good in 2022 and we got to the World Series. Of course he was also just as bad in that WS as Rojas was in the 2023 post-season.
It's not gonna be that complicated, it Rojas completely tanks (.550 OPS or below) he won't be in Philly by May 15th (or maybe even April 28th) If he's .600 or higher, playing his usual defense, and still having a good approach, he stays.
I personally think he's going to hit, opposing teams are not going to pitch (let alone scout him) the same way they did in the playoffs, and all the pitchers are still going to be finding their groove as well. If he'd come into spring training with no plan to work on and change some things, he probably would have hit in spring training too - but it wouldn't have paid off for him long-term.