V
Vale
Guest
Personally I find that an actor being much older than they should be or a role being recast is like seeing part of the set wobble or something fall off a prop.
Star Trek's already got form when it comes to "actor's ages not matching character's ages" though.
Patrick Stewart was 47 when he started playing a 59-year-old Jean-Luc Picard, and this age gap has carried consistently right through to Picard. Now, this is one I'm happy to handwave this as just "humans live a lot longer in the 24th century so they seem to age more slowly from a 20th/21st century perspective".
However, that doesn't work well as an explanation for actors who are obviously much older than their characters. 39-year-old Jonathan Archer was played by 47-year-old Scott Bakula; 26-year-old Kira Nerys was played by 36-year-old Nana Visitor; 25-year-old B'Elanna Torres was played by 36-year-old Roxann Dawson.