The side-roll makes perfect sense when you consider the game's control scheme as a whole. If you're playing the game as it's designed to be played, moving to the side while locking on and pushing the jump button isn't hard at all. You should be locked on and alternating your direction on the analog stick while you are attacking as well, so in context it isn't a bad design (it's arguably a good one if you can get your head out of what less complex games have been teaching you).
To be clear I don't think this control scheme is necessary to get the variety we see in DMC, but there are very few viable alternatives to get that variety. Changing the entire control scheme now when this one works about as well as the equally deep alternatives would be foolhardy, in my opinion. It might make more sense to experiment with that while making a new series, on the other hand.
If this is really annoying you that much and you're unwilling to adjust, just jump. It's easy, it's one button, just go with that until you feel comfortable diving deeper. But don't blame the game for your unwillingness to learn, you would be laughed out of the room for saying something like that about a fighting game, I don't see why DMC should be any different when it's really not that hard.