Gawd. I think you are right.
I was sure they'd brought in strict requirements last year specifying self-levelling systems, but all I can find on the DVLA site is "where fitted, the self-levelling system must work", i.e. if your vehicle doesn't have one it doesn't matter and you can have anything you like in there... and there is nothing new referring to motorcycles.
I was also certain that there was a maximum power limit on headlight bulbs, hence all those "not for road use" warnings on ebay listings for 100w bulbs... can't find anything in the MOT inspection manual for those either.
I think it's stupidly lax, no wonder I keep getting dazzled (as a shift worker, half my riding is at night). I certainly wouldn't fit them myself, I'm sure that it would only be a matter of time before I'd be part way round a left-hand bend and meet a little old lady in need of a cataract operation coming the other way.