I'm 35 years old and I've watched well over 1000 anime TV series and movies from pretty much every decade. I've also read around 400 different manga. The Frieren manga is mediocre, but the anime elevates the source material to such heights, thanks to its brilliant storyboard and direction, that it becomes a genuine 9 out of 10. SnK was pretty good up until the basement reveal and then took a complete nosedive into total shit. FMA was never that great but it's a solid show for kids. If you actually care about what anyone else thinks about the content you enjoy, you're an insecure faggot and very likely brown.