Hideous. I looked at these videos last night. Thankfully,I have a strong constitution and managed not to get too queasy.
The worst thing, for me at least, was the almost universally present problems relating to air conditioning / heating systems. This is something that hotel cleaning staff can't really deal with and the inherent risks of airborne bacteria and viruses - especially in more tropical countries - should be a serious cause for travelers.
Most of the other stuff - washing sheets more regularly, a bit hotter, stronger detergents (blah, blah, blah......) are fairly easy to resolve - if you employ enough / dilligent staff and give them / train them to use the right kit.
I suppose we should learn that if it doesn't smell right, change rooms - or change hotels....