An excellent article.
Bitcoin will be relevant simply because Wall Street Will deem it so. There will be a ton of money entering the space from this arena and bitcoin will be the biggest winner.
That said, I am a huge Charlie Lee fan and believe he was smart to go the sidechain route. The challenge BCH has is that it takes the power supply of a small nation to create a coin. Also, the 8MB blocks will create such huge volumes of data that the computational power will fight to keep up. According to one I read, we are talking Petabytes of data created...that is a ton.
It will be interesting to see which blockchains win out. Overall, there is room for many since blockchain will take over the world's economy. There is going to be so much put on these blockchains that it will end up being the foundation for commerce going forward.