There are a few items affecting movement speed and abilities that aren’t disabled by the Movement Items condo rule toggle. I don’t have an exhaustive list, but it at least seems to still allow most, if not all, vehicles.
The ability to use any vehicle can be used to either make jumps that would be too far for normal players, or clip through the floor and break out of bounds in tight locations, by rapidly equipping/unequipping the vehicle. As I understand it, the point of the Movement Items rule is specifically to let hosts disable movement exploits like that.
The most exploitable vehicle is the Ball Race Orb. It can be used to climb almost any wall at high speed, allowing it to be used as a sort of limited jetpack. It can also get a massive speed boost from push volumes, which can be used to push it through walls and out of bounds. It can also be used as a client-created custom spawnpoint, as its spawn seems to be (somewhat unreliably) set to wherever the player equipped it.
These issues allow players to trivially sequence break puzzle and exploration condos, and access secret areas, like admin-only I/O panels. I know, because I’ve done both. Teehee. 
I know suggestion posts have been made about this as far back as 2020, but considering the umbrella was added to the movement items list due to its exploitability, I feel that vehicles, but especially the Ball Race Orb, not being on the Movement Items list should qualify as an actual bug now.
Steps to Reproduce
Host disables Movement Items rule
Non-admin client equips a vehicle
Client can now zoom around at higher speed than host intended
What I expected to happen
Vehicles are disabled for clients.
What happened
Players can still use vehicles.