When i was beta testing i asked Berney Villers, why this mode was not implemented. He told me that it was hidden mainly because of two issues
1. De FFB of the wheel would not be in sync with simvibe
2. A lot of wheels can´t handle the forces of the transducers, so they were afraid that simvibe would kill the endusers wheels.
I fully agree with you on the lack of updates and support, which is a real shame
Last i asked about simvibe support on WRC3 and i got the reply that they don´t support a game that isn´t official for sale in the US. If somehow they could get hold of a copy they would look into it. A month later when you can buy the game anywhere on the world online, i asked the same question and never got a reply back.
I really hope we we see some updates and hope ALL the new sims will be supported.