Yeah, except... all the time. Sibling comment has an example about telecom in France. Google fiber. Low fare airlines which drove down incumbents' prices. This list is as long as the history of economics.

Competition doesn't always work. It isn't magic. It may even need assistance. But to say it never happens is just... not.

Of course it rarely happens. Let's say I say "go out and make a bus company that captures this market opportunity". How would you even begin to do it?