The reality (whether people want to recognize it) is that the public has never accepted or understood the games that the pool world has tried to push into the mainstream for the last few decades.
People who actually took the time to go to a pool match on youtube and attempt to watch it, and that took enough time to also read the comments and give their own opinion on the comment have said something that the pool world "should" take notice of as maybe being an issue. These people who are actually going to a pool video on youtube and attempting to watch it are likely more in tune with pool then Joe Blow on the street and they are STILL saying they don't understand the game. Something it wrong there, it is apparent, but the pool world yet again says "nah, we are doing nothing wrong, the rules are easy, it is there fault, we are not going to change" and thus nothing WILL change in this sport.
Could you take a deep breath and explain to me how the rules of 8-9-10 ball are more complicated and hard to understand than the rules of baseball, golf, basketball, and football? I think the answer is that the rules of pool are much simpler.
You should consider that there are possibly other reasons why pool is less popular than these other sports.