It's not simple in either direction. You have some events where responding faster is considered better most notably detecting input and some where you need a co

It's not simple in either direction. You have some events where responding faster is considered better most notably detecting input and some where you need a consistent frame-rate to avoid issues (e.g. simulating drag is really sensitive to framerate and will behave quite differently as a game slows down). A fixed timestep also causes the game to slow down if it can't hit the desired update rate. FWIW neither Unity nor UE4 use a fixed timestep for their default update and tick.