I mean, it was groundbreaking for its time and it redefined the genre and a lot of moviemaking in general. But yeah, it had severe pacing issues, is undeservedly way too long and it got way too trippy and abstract by the end. Frankly a whole lot of it feels like Kubrick masturbating over how great he is, with a lot of scenes being way too long and serving no real or useful purpose on on the movie.

I could say pretty much the same about Solaris too (the original Tarkovsky version which cinephiles always rave about, not Soderbergh"s, which I actually prefer), and if rumors are true, apparently Kubrick took a lot of ideas from it.