Non-mining-related nodes don't matter. Transactions will reach mining nodes/pools. Non-mining nodes are only interesting for its owner, to see the block chain for himself, and verify its validity without having to trust another full node. But full nodes that do not relate to mining don't matter in the consensus mechanism.
What does matter, are users. They 'vote with their money' and determine market cap.
you have been sold alot of BS
1. exchanges are the nodes. if they orphan block X.. your TX in that block doesnt exist = you cant spend because they dont see it
2. if a friend is using a node and you pay that friend. if they orphan block X.. your tx in that block doesnt exist = you cant spend because they dont see it
with each node calling out the blockheight. they all grab data from the highest block height. if that blockheight is blocks of rules that dont match
then they orphan those blocks. and end up unsynced.
the only way to sync is either change your rules to rejoin the majority.
or.
BAN the majority to not see the block height to not be endlessly clusterfu*ked to then start building on a minority that you can accept.
if you dont ban. your minority is not treated as a valid chain due to it not having the height.
its a security feature.
otherwise someone could copy the blockchain. kill off say 2 years of blockheight and then just build ontop of it.(at a healthier difficulty) and then build their own chain
but that requires not communicating with the rest of the network by banning the nodes following the highest blockheight, so that the blockheight mechanism doesnt kill off the minority due to the minority height reject mechanism.
like i said many times it involves intentionally banning nodes to not see a bigger height. otherwise orphan games begin fighting over the rules