Valid transactions are enforced by nodes, not miners (there are WAY more nodes than mining pools). All of a miner's incentives persuade them to mine on the lon

Valid transactions are enforced by nodes, not miners (there are WAY more nodes than mining pools). All of a miner's incentives persuade them to mine on the longest chain, lest they lose out on potential profits. A group of nodes and miners can certainly fork if they please, but the network simply won't care. e.g. BCH/BTC