I just watched the string fuel video. Horrible performance by the 'actor' and the product seems silly. The majority of the gunk that builds up on the strings is located on the underside of the string between the string and fretboard. How could dragging a sponge across the topside be effective? The idea of applying oil to a wound string seems problematic and not much different than applying the natural oil from our clean fingers. As mentioned, wash your hands.
I know quite a few use 'oily' products or baby powder. I have seen Jeff Beck and Ronnie Wood using powder. For me, powder makes a big mess and provides very little benefit.
I don't understand why the finger squeaks are such a 'big' topic? For me, it is easily improved through good technique to the point of not being an issue. Sure, certain profiles/EQ can highlight it, but I would argue those are bad settings. Steel string acoustic guitars are the worst IME, and are a good platform to develop anti-squeak technique. Some squeak is unavoidable especially with round wounds.
Guitar setup matters to me nearly as much as technique. It all matters. Nut slot depth, string height at the 12th, neck relief, level frets and intonation. A well set up guitar can make or break a situation. My acoustics are all set perfectly. I'm not there with my electrics yet, but I will soon be. I'm dragging my feet on the nut filing front.
I have never played a guitar where the setup had any influence on squeak. Yes, setup matters for playability which is what you are referring to? Interesting that you have acoustics that are setup perfectly. I don't believe I have ever played an acoustic or any other guitar with a perfect setup. There is no acoustic guitar, or any guitar for that matter, that is perfectly intonated in all keys. Such a thing does not exist especially considering Western tuning. We are subject to that problem. The player must play the instrument so that it sounds in tune. I have had many other guitarist play one of my guitars and make the tuning sounding horrible. Yet it is in tune when they hand it back to me.