I'm afraid to say that physics are very broken / simplistic and remind me of UE4 wheel physics tutorials.
The walls are very sticky as if they have a layer of glue, not kicking the kart back when driving against them. Compare the collision of Brodi with the downhill wall in these two videos: Remake and Classic.
It's like there's no reaction on / noticeable resolval of collisions. Many gameplay videos show hitting other karts which plays the collision sound over and over until you resolve the collision by normal driving means. That feels like a rookie physics error.

Also, where's the chat? I see no chat in the lobby or game. That will definitely kill the game for me. It feels like racing against robots, as in Mario Kart 8 with those useless predefined messages. Socializing in this game is one of its core features which puts it ahead of other fun racers.
And because of this, the missing player avatars / karts in a game room / ready stage and game lists also need to be reintroduced as in the classic game, currently you only see pseudonymous names and apparently get auto matched - boo.

Since Nexon Korea apparently still applies bigger changes to the game (the video captured by the OP is from a later build than the one shown in XO19, note the new item icons), I have hope things get changed for CBT or at least OBT given the short time until CBT is out.

See you on track!