I was with you until you said the street tires are supported by high hp cars argument. the handling advantage of a good handling car is magnified on lesser tires, and top speed is higher, too. but I've just driven the things for 4 years, on my IT car, in Hoosier fields. I don't know what I'm talking about.
and, FWIW, I'm largely against the proposal. Not becasue the tires suck, I like them. It's because of the difficulties, real and percieved, and the lack of REAL differentiation of IT or a clear path for those in IT who DO NOT want to continue with 200TW IT to remain competative with minimal added cost or modification. I AM in support of a newer class between Touring and IT specs using 200TWs, as a path for street AX and trackday guys to come in to club racing.
the crapcan series success has a lot more to do with "different than SCCA" than the tires. the tires are part of it, and there's a psychological component there, I'm sure, but they aren't the magic bullet.
what these tires WOULD DO once everything has stabilized around them is reduce the benefit of spending money on tires vs. those who stretch their budgets. anything we can do to reduce the benefit of spending money helps bunch the field up. I loved driving on 200s my package: 205/50R15 Dunlop ZII and ZIIss, 15x6 and 15x7 wheels (2017 rules change) ITB MR2 at 2340-2400 lbs, 400/450 springs, Koni RACE inserts, ST bars, ~105 hp, stock 4.3 final drive. They force you to be smoother, are easier to recover when you over do it, and don't suffer as much from lockups or slides as the DOT-Rs. they were plenty of fun and MADE ME A BETTER DRIVER. I got to my old SM6 times at sebring on them, and when I bolt on R7s now I am a lot faster than I used to be (with room to grow because I'm not used to them). and I never had to worry about heat cycles or weather or not I had tires. do they go off? yes. they slime up in a session (can be cooled) and they eventually hit an age wall (may be improved with storage) where they suddenly just SUCK even though they look fine. I got 3 years, 1/2 of a lemons race, and 2 weekends on a civic wagon at RRR on 2.5 sets (the half set is the one that sat for a long time and gave up on me - but I still ran them for 2 hours in a Lemons race). I saved a BUNCH of money vs. hoosiers.
But even knowing all of that, I think forcing them on the class with no other changes to prep rules, overall club racing strategy, or category philosophy is a bad idea. I'm not against what some people envision here, I'm against the idea that this is a solution. we have problems, 200TW tires may be part of the answer, but I think piecemealing parts of a solution outside of a cohesive strategy can do more harm than good.