a dirt bike with a fancy name that would kill anything in corners. yes they arent a sportsbike, but at least they arent a pretend sportsbike (ninja 250r).
look, i've got both a motard and a sportsbike and they both have their upsides and downsides. but in the LAM's situation you cant find a faster bike. and if you're a learner, they cost next to nothing to fix if you crash and you can jump them big. not sure how many sportsbikes of any type can jump 100ft and not break or bend anything.
for any tracks or roads where you stick under 160km/h a well set up supermoto will be faster than a well set up sportsbike. so at a track like broadford theres hardly an advantage to a sportsbike. but obviously at phillip island you would have no chance on a supermoto compared to a sportsbike.
different bikes for different situations, but for a LAMS and streetbike, the supermoto has more usable and greater performance. but they arent for everyone, as people like yourself do not have the brain power to understand why they are how they are, and usually the people who dont understand them couldnt ride out of sight in a dark foggy night..