As i said, there are plenty of bikes that make tons of power, but only the SS get the bad rep, and therefore the short stick as far as insurance is concerned
I can list many
Sure, but look at who's riding them.
Supersports tend to attract a typically risky segment of the riding population - young testosterone laden males with ego's. Yeah, not all SS owners fit that stereotype, but a huge segment do, and so the risk is high for insurance companies.
When that segment figures out that they can't afford to insure that GSXR anymore but CAN afford to insure the near-equivalent naked equivalent, well, as I said, that doesn't change the mindset of the person behind the handlebars, and it doesn't much effect the ability for them to do stupid things on a bike that is nearly the equivalent of the SS they really wanted.
So, it comes full circle to the risk stats. As the nakeds begin to attract a larger and larger share of the hooligan population, you'll see their insurance costs go up.
If every 20 year old male boy racer with a chip on his shoulder suddenly decided that Vstar 650's were the new hotness, well, I'd guess that eventually insurance on Vstar 650's would react accordingly, since the statistics would suddenly start to show all sorts of wrecks on Vstar 650's. Again, it's the person behind the handlebars making the decisions.
Power or CC's isn't always the biggest factor...again, it's that person behind the handlebars again, and the SS's attract the young high risk ones. You CAN insure a SS on the cheap - I have a friend riding a litre SS but because he's got 20 years of full M experience, a clean record, and is in his mid 40's he's paying little more than what I'm paying for my 1300CC cruiser, speaking of which I pay only $500/year for.
The Boss Hoss is a great example - it has a V8 under the tank making nearly 450HP, but an experienced rider can insure it for about (or under) $1000/year, but the insurance companies know that they sell to a very low risk segment of the riding population who are more apt to be cautious and safe riders (and can actually afford and appreciate a bike like that), hence the low cost.