[barnstenchfartface]

It makes sense if we take into account that the main purpose of the Level 1 forms--of the Gamer Driver, really--is saving people by defeating the Bugsters. Level 1 specifically is designed to do this with the initial manifestation of the Bugster virus. It wouldn't make sense for the Buggle Driver to replicate the Level 1 feature, being Bugster tech, and Paradox doesn't use the Gamer Driver either.

At least, that's the in-universe reason they've already sort of worked into the story. Even outside of all that, though, I figure they decided while designing this stuff that Level 1/X forms would just be Gamer Driver things. Paradox even has his own back-gimmick based on the Gear Dual, as he apparently has a big gear on his back that changes his forms when turned (somehow).