Got a counter offer from my current manager and it made the decision harder, not easier

External offer came in with a solid bump, brought it to my manager mostly as a courtesy, not expecting anything back. She came back within two days with a matched number and a promotion timeline that had apparently already been in the works. Now I'm choosing between a known team I like and a new place with more money and zero history. Money isn't actually the deciding factor here, which I did not expect to be true.