BIP91 supersedes BIP148. They are planning to implement Segwit2X, which is a hard fork, on Nov 1st. However, if 100% of miners support Segwit2X, then there will not be a fork. It is very unlikely to get an 100% consensus among the miners so a fork is very likely.
As they said that lightning network can be implemented on Segwit which can solve the transactions speed issue, then an increase in the block size is just a way for miners to get more money from the transaction fee in the short run. I do not mind that the miners are getting more money, but a hard fork from a Segwit2X is very concerning.
I believe thing will reach to an equilibrium or closed to equilibrium. Even with block size increase and with Segwit implementation, it will still take 10 mins to process one block as the difficulty level will be adjusted to make it so. In the beginning, if the mining becomes more profitable, more miners will join to make the mining pool and bring down the profitability. So given this plus the potential Lightning Network implementation, I really do not know if Segwit2X is really necessary.