You’re correct. In addition you could strafe using left/right C buttons, and you could look up/down using up/down C buttons, but that was awkward and not really designed to aim.
But we also must remember that those games had an auto lock system. Your character would actually target the ennemies by himself, you would only use the crosshair to dona headshot when you have time to aim, or to aim at a specific object in the game.
But yeah, that seems so clunky compared to what we have today