You are missing my point. It does one thing. Protect. You'd have no way of knowing how it did until years later. Being garaged like yours is, you might not even need the stuff. But it is cheap insurance, for sure.
I get your point about "protection". The thing is there are all but countless products out there that accomplish the exact same thing. They will also "protect", while improving the looks of where they're applied, to the point you can at least see it.
This crap is like wiping on water. It dries and it's gone. You can't tell it was ever applied. So why bother using it, when you can apply a similar product that will improve the appearance of what your putting it on, while "protecting" it as well?
The whole concept of washing, waxing, and detailing a vehicle, is to have it look better when you're done, than when you started. Not look the same.
I get that people don't necessarily want a high gloss shine. But I've never seen
any black plastic trim that doesn't look better with some type of dressing on it that richens up the look of it, all while "protecting" it as well.
And most all of these protective dressings are available in a formula that will produce any type of look you wish to achieve. This crap is completely useless in that department.... Regardless of how well it supposedly, "protects".... Which they all do.