There is a huge difference between being "licensed" and being "recommend for use in ..." or "suggested for use where ..."
That being said, in no way does that mean the unlicensed fluids are bad, nor applicable. It simply means they are not guaranteed because they are untested (or tested and failed) by the licensor. Unlicesned fluids can meet/exceed specs, or they could flounder miserably. Licensing is a way to provide assured performance and/or chemisty criteria are met. If you choose a licensed product, you are guaranteed a minimum level of spec being met.
Unlicensed fluids can certainly meet/exceed specs, but they are not typically guaranteed by the equipment OEM, but (most often) by the aftermarket manufacturer.
I have used both licensed and non-licensed fluids. Each has their place for particular reasons. Everyone has a threshold that they prefer not to cross. It's not that one is perfect and one is evil, but rather that each fits a perceived "need" of the customer for particular applications.
An example we're all familar with is the whole DEX III/Mercon issue. "Dexron III" and "Mercon" are no longer licensed by their respective OEM licensors GM and Ford. Now, because they were w-i-d-e-l-y used in the whole automotive market, even by some Japaneese products, they are still called for in the marketplace; there is still a huge demand for these basic fluids.
So many lubricant manufactures make "DEX/Merc" or "D/M" or "D3/M" or some other product that uses a familiar moniker, but they cannot use "Dexron III(h)" or "Mercon" because those fluid licenses are not issued any longer. The aftermarket lube makers can choose to continue make the products as though they would have met those former specs, as if they were still active. But they also could choose to skirt around those specs or otherwise cheapen the products, because they no longer have to live up to a "standard" set by the license. Unlicensed fluids can either be bad or good, but licensed fluids are assured to meet a certain minimum standard set by the licensor. For unlicesned fluids, it's caveot emptor!
So, how does this pertain to the DEX VI issue? Well, unless I misunderstand, DEX VI is not only performance based, but also chemistry based in it's licensing. As I've often touted, to be DEX VI you can't just walk or talk like a duck, you have to be a duck at the genetic level. So any licensed DEX VI product will suffice to the standard GM set. To meet the performance criteria, it's pretty much a given that the fluid will be at least, in part, a group III type blended product. Some companies, such as Valvoline, may choose to go to a "full syntheitc" base stock like all group III to "exceed" the spec, while others might use a semi-syn blend to meet/exceed the spec. The chemistry is also very important for DEX VI licensing.
If it's DEX VI licensed, it's a fine fluid for any application that would officially call for it.