You know, you may be onto something there. Maybe it's less about taking this stuff literally than about taking it more
personally than before. As though recasting a part in a popular franchise is somehow "disrespecting" the audience or whatever. Look at all the hyperbolic language you see about how some given movie or tv episode is "a slap in the face" to fans.
I was disappointed when they recast Saavik back in the day, but I don't recall taking it as a personal affront.
And, honestly, Valerie Hobson was a lot more appealing than Mae Clarke back in the thirties.