“Bitcoin mining pools are critically centralized and it could be existential to the network if miners don't act.” - @MartyBent 

https://www.tftc.io/bitcoin-mining-pool-centralization/ 

 Will eventually de-centralize
https://www.youtube.com/watch?v=AA5FdM4WGKQ

gridless mining
https://www.youtube.com/watch?v=fKkw5qfcwRc