I was a tire tech for six years. Maybe I can dispel some over complicated thinking.
1.)You use soap and water as lube on a machine mounted tire. Too much soap and it stays slippery.
2.)There's generally a film on new tires. We were always told it was to help preserve new looks of the tire in shipping. It's slippery as hell. Walk into a high volume tire shop and look at the floor next to the tire rack- it will never need to be waxed, I promise you.
Yes. New tires are slippery. They haven't abraded any and the rubber is only contacting on the slightly less flexible first .001" of rubber than every bit of tire beneath it.
If you heat the tire first that's generally fine too as it softens that exterior just the way it does the rest of the tire. Guess what- recreational amateur riders don't heat their tires before leaving a store and the store sure won't heat them, either.
Simple green can degrade some rubber compounds a bit excessively for this purpose. 1:10 dish soap and water and a soft scrub brush is absolutely just fine for the film and the mildly tougher first .001" of tire won't be so significantly different as to be dangerous without it.