>>55589106
I'd say 38 is more than enough for a 'fair chance'. I personally wouldn't, but if you want to yourself then that is respectable.
If a genre doesn't interest me after around 15 or so 'classic' albums then I wouldn't want to continue. For example something like shoegaze shown here: if you really don't like all three albums in the middle, then wouldn't that mean the genre isn't really your kind of thing?
But for hip hop you can't summartise it into three albums, as it is just so big. Listening to 38 you don't like is a bit excessive though imo.