Sometimes one just has to hope. It would be nice to do a test out in the desert where half a hood has sealant applied and one half is left bare. Apply sealant on a regular basis and see what it looks like in a number of years or months or whatever. It just seems to me the manufacturers claim UV protection but never have any proof to back it up. We need someone like David from optimum to come on and clarify. He claims UV protection in his spray wax.
Nu Finish did a commercial years ago on a UV damaged car hood in the desert. Brought it back to a showroom shine Im the MAN