Yep, twenty years is night and day!
I had to hop onto Facebook last year (to see what rentals were listed on the local facebook group), and got bombarded with people’s profiles from my high school graduating class. They mostly looked horrendous to me because I remember them from 20+ years ago.
There’s a guy at work who is my exact age, and I showed him some of the profiles and we had a good laugh. They looked like they had grandchildren, and actually, a few of them probably do.
But we were also aware that someone seeing either of us for the first time in 20 years would probably be similarly horrified.
Just for fun, do you remember a pop singer named Basia? Eastern European heritage, looked like a model. Now in her 50s, she looks nothing like a model or a former model. (Do a YouTube search for the before and after).
I think it’s cute that the girlfriend thinks your 30 year old self is hot. Definitely take it as a copliment!