This is the reality.
BTC Miners => 4 Mining Pool operators = security is dependent on 4 guys with over 51% attack vector.

your non-mining nodes do nothing to secure the network.
Just so I've got this straight, you want to present the simultaneous argument that Bitcoin is centralised due to a limited number of miners and also that a distributed network of non-mining nodes don't help at all with securing the network? Is that correct?
Bitcoin is centralized due to the Mining Nodes decisions to Pool over 51% to only a few pools.
The problem is the LIMITED Number of Pools, not the number of mining nodes.
As if their were no pooling, then a mere 4 guys would not control bitcoin.
Remove pooling and that issue is solved.
Sad, your IQ is so low that had to be explained to you.4 "guys" control Bitcoin?
Yes your non-mining nodes are as useless as you are in a debate. 
Then why can't the miners control a network of non-mining-node-running-basement-dwellers?

FYI:
Miners have power because they can control the network.
Large Holders have power because they can use economic clout to sway the miners.
Idiots that run non-mining nodes, just to claim they are important, are utterly powerless.
Case in point idiots that run non-mining node have been wanting to receive some compensation for years,
and they still receive $ZERO.
No. When non-mining nodes say they want a kind of block that the miners cannot provide, then the non-mining nodes will reject those blocks.
Happy 2nd anniversary Segwit! #UASF.