Open source schematics and a closed Supercharger network until this year, at least in the US. It's hard to separate Tesla's intentions in opening up their charging network from the legislation in both the US and EU incentivizing it.
No they did actually follow through on the charging stuff to the point where NACS is now the new north American standard, which is kind of wild to see given how they've acted before.
Funfact: NACS ist just CCS with a different physical connector. You just need to read and understand the specs.