What time length is ideal for a hip hop album?

I think albums should be about an hour long.

You can pull off a short album (40 minutes) if it's all great material
(Illmatic).

Long albums are never good. They're fatiguing and have a lot of
filler.

Double albums are also not good. There are some great hip hop double
albums but they could all be cut down to a single disc and improved.