In theory where everyone 'owns' a little piece of hashing power and we don't have whales controlling huge amount of bitcoins - in this situation bitcoin is safe and indeed are free from manipulation.
But we are reaching the state when bitcoin will be controlled by large centralized mining farms as they will provide majority of the hash power.
Miners can't force the rules on the node operators. Miners actually have no power without the users. Their hashrate and coins would plummet in value very quickly if they did something malicious.