Mining is an area I understand very little of, but I'm surprised it wasn't foreseen that behemoths like Bitmain would rise and something wasn't done to attempt to address it before it happened.
Satoshi predicted it. He simply said people should be nice and hold off doing the inevitable... The rest of us predicted it too but there isn't actually anything we could do to "address" it as you have said. Bitcoin is a diffuse collaborative and there are no weapons to defend us against transient centralisation of power and hashrate. Proof of work will inevitably
ALWAYS have some element of this happening at regular intervals. Changing the proof of work algorithm will NOT, as the article said, make any difference at all; a new asic arms race will simply replace the old one.
Probably the biggest mistake everyone makes is buying stuff off bitmain only to find themselves competing against bitmain... duh.