A cynical move: the aggregator API rug pull.
Make an API to become the obvious schelling point… and then remove it.
Amazon, Facebook, and Twitter all did this.
How it works: there's a growing 1P platform that then opens up an API so 3Ps can build on it.
It's much easier for a 3P to hitch a ride than try to compete, so they build on the API.
Later, once the 1P platform has passed critical mass to be unstoppable, the 1P says "oh oops actually we're getting rid of the API."
Now it's too late for any other competitor to get going, and all of the 3P energy was absorbed onto the platform and then killed.
The gradient for adoption is gone, the ladder is pulled up, and all of the 3Ps are left in an inhospitable desert wasteland to starve.