This isn't true. A protocol change would require every Bitcoin user to change their software. 51% regards miner based attacks on the network such as double spends.
Miners still have to obey the rules of the Bitcoin nodes. If a miner tried to generate more coins, even if 100% of miners tried, it would fail as the several thousand active Bitcoin nodes would simply reject the blocks.
Miners still have to obey the rules of the Bitcoin nodes. If a miner tried to generate more coins, even if 100% of miners tried, it would fail as the several thousand active Bitcoin nodes would simply reject the blocks.