I don't think he looks that old, and I do think that people thinking that (and thinking he dated Donna while she was his student) indicates they don't know the character/material very much, and so their opinions on him aren't worth as much to me if they don't even get correct the most basic information about him. I mean, whey they say they dislike him for dating someone 20 years younger, dating his student, or hitting on other women in front of Donna, and I know all three of those to be false...I mean, some people in this forum though he was 40s, while Donna is 20s.
There are reasons to dislike the character, I just don't like people saying he did things he didn't when explaining their dislike.