That's not true. You could just as well say that there is number of exchanges in the world that trade Bitcoin against USD and other currencies. It is this trade that give Bitcoin value, and only the Bitcoin fork the exchanges use is valuable. If all the miners would fork Bitcoin today to change consensus (perhaps to earn more from mining), and all the users and exchanges stayed behind, that would only be visible as a drop in mining power. In reality it's much more complicated, and consensus changes are not to be made lightly.

The exchanges wanted to fork to increase the bandwidth cap. The miners refused. You can see who won.

That does not mean that miners dictate which fork to use. The opposite situation, that miners wanted bigger blocks but exchanges and users refused, would be similarly impossible. It's a bit like mutually assured destruction, nobody wants to see a big drop in value.

At it's core, the true bitcoin is the bitcoin that "can be exchanged for goods and services" (and other currencies).