Slasher said it didn't seem like it was in there when he played it, and I recall a few other conversations where people said it wasn't there on discord. Pretty sure it's not. :'(
considering how game engines handle physics, simulations & network nowadays, wall clipping will surely not be present. It was only a result of cutting corners (not intended) in simulation + networking in q3 to be light on computation.
Whatever their motivations for coding it that way, it also had the rather desirable effect of not making you feel like you are a giant cuboid, where you get stopped in your tracks if so much as a millimetre of your bounding box hits a wall, even if you're going at 2000ups.
It feels more organic because you could believe you are adjusting your body as you go past, to cut the corner as close as possible.
The body is represented as a capsule. (at least that's the trend, so it's safe to assume) Colliding with a corner should push your body a little bit away, and change your direction (amount varies depending on the angle and how much you hit the corner), but shouldn't stop you completely. Yes, different to q3, but don't think this should be a game-breaker as it could make some new tricks possible. But time will tell.