FAR 101.41 (b) subsumes any such guideline as a regulation. AMA's see and avoid guideline says any flight expected to go above 400 feet requires a spotter, so if you don't do that, you're violating FARs. Operating an sUAS with autopilot (among other things) has its additional advanced flight system programming guidelines, which have a hard 400 foot ceiling when operating within 5 miles of an airport. This is legally identical to having a regulation preventing operation above 400 feet AGL.

If you violate the applicable community guidelines, you're violating FARs. That's what this part says.

And then there is the catch all FAR 101.43, which is a big black hole of liability that you can also easily run into if you're unfamiliar with the national airspace system and your surroundings. If you fly a sailplane or m/sUAS above 1200' AGL in a published victor airway (this is Class E airspace), I'd argue that's a clear altitude violation of this regulations.