In Windows 7 x64, If I start a sigle player game and try to enter even the most stock vehicles, nothing happens. I can't get into neither the driver nor the gunner seat. Passenger seats work.
v2.19 was working fine (well, only in 32 bit mode due to unsupported Intel instructions being used in the x64 executable) .
The version before 2.19 was working completely fine.
Start the game, enter any single player mission, try to drive a car. Nothing happens. Same with the gunner seat. No crash is observed, the player just doesn't get inside the vehicle but can continue doing other things, such as managing the vehicle inventory, firing, moving around, etc.
Attached you can find the .rpt log of a very short game in the NATO showcase mission,
Notice the many lines warning about Steam API not working in Windows 7, which I suppose will be a different issue, and thus I have reported it separately on T192972
Additional logs available on request.