I don't know whether they've implemented the new movement system yet, since the movement still feels like it's the same old controllable one. If they changed something, it was pretty minor.
That said, I'd welcome any change that makes people move more like actual humans rather than crabs.
Just consider how you'd move as an actual human with a backpack and gun.
You're not going to stop on a dime from a full sprint, or walk full speed sideways while aiming a gun. Nor for that matter are you going to walk sideways or backwards at any speed when crouched.
The change is really minor and more of a small adjustment for players than anything huge. It makes the movement slightly more realistic and believable and improves the game for the better in the long term by removing some of the cheesier stuff.
That part, the one where you can't strafe while in the middle of sprint and carrying a ton of equipment, is intentional. It makes the movement actually feel more realistic and tones down cheesing of the movement system.
It shouldn't have been possible in the first place; bodies, especially bodies loaded with equipment and ammo have inertia. You try crab walking like doom while doing that and you'll fall down or break your legs.
Just avoid naruto running in the middle of a firefight and you'll be fine. It'll take a but of adjustment, that's all.