Acrylic conformal coating is made to create a barrier, but also be easier to do rework on. Silicone conformal coating is more tough and much harder to do rework on. It's much more difficult to remove if you need to replace a component on the PCB. If you don't plan to do rework/repairs to the board. Go with silicone. If you want to be able to repair the board without the difficulty of removing the silicone, use acrylic. It's made to allow the heat of your iron to eat through it and make the repairs you need.
It does appear that the silicone is more durable but as with any coating, surface preperation is critical. I would have liked to see the board washed in alcohol first.
Not sure where you're from but I had to watch this at 1.25-1.5x speed. :) Jokes aside, when you were picking at both sides with your fingernail, I have to say it was a little biased. You scratched the acrylic at the edges of the areas that were already flaking vs the center of the silicone side. But you are right, the review corroborate your experience with this. I will be getting the 422B silicone spray thanks to this video.
I can tell you for a fact you didn't properly prepare the board cleaning it etc cuz I've used that shit for years and even nail polish and it doesn't come off like that and just hearing and looking at your board yeah that's like painting a car that's covered in dirt and expecting it to stay
