I'd forgotten about Brees (he made it to 41), so you're right in that it's not just Brady. But, while Brees was still a viable QB during the regular season, his arm had declined to the point where he was a playoff liability. Brady's still the only recent QB who remained a legitimate SB threat into his 40's.
What does play in Wilson's favor is that he's long since learned that, when running, discretion is the better part of valor, and he gets down before he gets hit. That should help keep him healthy for longer than he otherwise would.
And just a note about your thought about a trend:
I do expect that Rodgers will still be a (theoretical) SB threat into his 40's. I would just add the note that he's Aaron Rodgers, which means that he's still likely to spit the bit at some point in each playoff run.