What is your opinion on the "no anime before 2010".

Personally I don't get the hate for old anime. I think Cowboy Bebop is a great show, it has good music, the animation is good and the story is interesting. I only started watching anime around 2013. And until 2018 I mostly focused on new anime to be released that year. But this last year I have been watching a lot of older anime, from the 80s and 90s and to be fair it is not bad. There are some which are definitely bad, but there are good ones too. What is your opinion on it?