Maybe this was sarcasm, I'd have to read more from the previous discussion to tell.
In case it's not: It shouldn't be surprising mining is becoming more centralized, seeing as Bitcoin appears to have been designed with that expectation:
https://bitcointalksearch.org/topic/m.6306
" The more burden it is to run a node, the fewer nodes there will be. Those few nodes will be big server farms. The rest will be client nodes that only do transactions and don't generate."
('generating' being what mining was called way back,)
So yeah. From that, it seems if you want highly decentralized mining, you should take a hard look at whether Bitcoin is suitable to your purposes.