Yes, if we go by actors' ages, Brophy himself is too young to be credible in the role. But in my head canon, humans in the 24th century age a little more slowly than we do. Kor
There's no real need to resort to head canon for that: just look at Picard himself Vs. the actor who plays him.
Brian Brophy once asked for a submarine sandwich with everything. The deli served him an Ohio-class strategic missile sub with 24 fully-loaded Trident II D-5 missiles.
Took me a minute. I kept thinking Sisyphus. The boulder would insist on rolling itself up the hill while Brophy enjoyed a cool drink in the shade.
No no no no no. Using an 80-ish actor instead would make Bruce Maddox's affair with Agnes Jurati, his former student and half his age, even more off-putting. No offense to John Ales, but if Brian Brophy had returned to the role, no one (and I do mean no one) would wonder why Agnes jumped her prof. Then again if Brophy had been cast, no one would believe Agnes wouldn't be all over Maddox again. Actually Bjayzl would have kept Maddox for herself instead of trading him. Then again, let's be honest, after 14 years or so isolated with Bruce and the kids on Coppelius, Altan would never willingly let him offplanet. Wink wink nudge nudge, know what I mean? Because Brian Brophy goes. Anyway, recast solved. It was absolutely needed for plausibility of PIC plotlines. Say no more.
Don't let it be forgot That once there was a spot For one brief shining moment that was known As *Camelot. *A Brian Brophy Production.