[jlg23]

I've found bishops to be more useful in end games because they can block whole diagonals and thus I will gladly exchange my knights for the opponent's bishops. Knights can be easily outmanoeuvred - it is easy to render a knight useless for one move and thereby gain some space to turn a check against you into a more favorable position.

[edgarvaldes]

But if the endgame has blocked pawns, the knights vs bishop is a lot more nuanced.