That's not everyone wins. The people that actually bought these devices now have cables that don't work and need to replace with a lower quality product, and the people who were already using something else are continuing to not need cables for these devices. The majority breaks even, a significant minority loses.
Simply not choosing one cable to rule them all lets everyone win. There is no compelling reason for one size to fit all.
If some people like hip hop but more people like country, it's not a win for everybody to eliminate the hip hop radio stations so we can all listen to a single country station.
Further, rail gauge is not a consumer choice. If there were two rail gauges and your local rail station happened to have a different gauge than your destination, you'd be SOL. A different rail gauge may provide benefits for people with specific needs, but you don't get to take advantage of those benefits except by blind luck.
There is no such benefit from standardizing cable connectors. If someone charges their phone with the same style cable as you, you gain nothing. If someone uses a different cable, you lose nothing. There is no reason for anyone not to use their preferred cable which is optimal for their use case.
I'm sure there are more than a few people that would end up throwing out their perfectly functional accessories, only for the convenience of carrying less cables.
I don't want to ship another cable across the Pacific Ocean from China so I can have a cable that works on my devices.
I want to keep using them until they don't work and I can't repair them any more.