It's not the 'noticing' that's the problem, it's the verbalizing of those thoughts, the public audience, the assumptions. This is a joke, right? Do so many not really see this?
No. I don't see it. I've been told I was handsome, pretty, good looking for 50 freaking years and never once took offense. Maybe in the context of a chat room like this where someone says it, but in real life noticing and verbalizing that a person is pretty or handsome is not judgmental nor is it offensive.
It's not a joke. People need to grow up and realize that we are humans and we think with our eyes, our ears, and sometimes our brains. The world is not blind and it's not offensive to say "wow, that's a beautiful camelia".