They can certainly try, but miners are at the whim of market forces (just like the rest of the world).

Everyone holding bitcoins before the miners "do something" can sell these new "whatever the miners want" forked coins and buy actual bitcoins with the proceeds. The smart kids will mine the valuable coin while the we-are-trying-to-push-rules-on-you crowd will be stuck with a bunch of worthless tokens.

Miners only make money because people value the properties of the current block chain and are willing to exchange other things of value for the bitcoins which exist because of that block chain. I keep hearing long-time bitcoiners talking about the power miners have when it's obvious that the economic majority has all the power.

If no one will trade other objects of value for whatever it is the miners are selling, I can promise you that the miners won't be selling it for long. Miners have no power.

TLDR: No.