anidb says 464 (counts different seasons and OAV from the same anime as one single anime, so I watched a lot more), 7285 episodes, about 3.19% of existing anime.
https://anidb.net/perl-bin/animedb.pl?show=mylist&uid=48425&pass=guest
There are probably some I forgot and didn't add to my list, either from 80's or the one I watched from netflix/stream plateform.
I used to watch a few every seasons, by picking randomly and keeping the one I found interesting.
I didn't watch a lot for few years now due to missing time. I didn't even follow what's released anymore

I watched most between 2003 and 2014. I miss it.
recently watched or still following:
attack titan
Eden
Natsume Yuujinchou
Boruto
Edens Zero
fairy tail (currently watching FT2018 (50 ep left) before netflix remove them in 5 days)
One piece (200 ep late, I'm reading it instead)