don't want to call it 'rap' because he uhh... doesn't rap a single bar.

and he isn't really singing either, so it ain't 'r&b' (new genre name desperately needed for the last 20 years...)

but yeah, this is a classic record in the sense that like you can play this in 5 years and it's going to be as good as it was in 2015.

really a tranquil, relaxing beat.
good vocal performance to match.

synergy and successfully evoking feelings makes great songs.
this definitely qualifies, imo.

<- way before hashtags.