It's not your only option. Kyosho, Tekno, Mugen and Agama have viable choices in Truggy. Serpent has one in development that should be out soon.
Truggy isn't all that popular anymore, the counts are lower than Nitro Buggy and E-Buggy at all the races, club days or otherwise. They don't even have the buggy right, so I suspect that the Truggy is not a large priority for them at the moment.