We, the consumers, could
We, the consumers, could agree on a standard. However, if "we" includes manufacturers, some of them want to muddy the waters with competing standards.
For instance, Chrysler/Fiat doesn't believe in EVs. The only make one, the Fiat 500e because they're forced to, but they don't offer a quick-charge port on it. If they had voted for CHAdeMO as a standard, it would have strengthened pro-EV competitors like Nissan due to the thousands of CHAdeMO stations already in existence. So, naturally they voted for a standard which is nearly vaporware for the moment.