The vast majority of people aren't aware of open versus closed protocols. If enough people they want to communicate with are using it to counterbalance how frustrating it is, they'll use it. It happened because businesses realized there's profit in lock in, and they threw resources at it.

Open protocols are still there and still used, but we're sad because the smaller userbase is frustrating. Just like how people still publish human written content to personal blogs, but they're proportionally non-existent.