I didn’t play much of the original three Halo games, I picked the series up when Reach came out, but yea movement and controls were simpler, there was no sprint or the special abilities they added in reach and afterwards like the jet pack and place down shield barriers. It was just you and your weapon against the other dude and their weapon.

If memory serves the original halos actually felt slower in terms of movement and time to kill than the modern ones.