It's the US where there currently isn't a strong "second place" to Tesla yet. There are a lot of competitors depending on region, but that's also the problem is that there are so many competitors that quality is a very broad spectrum and margins are low. VW's (US EPA mandated) Electrify America (and its alliance in turn with players like ChargePoint) is probably the one to watch for up-and-coming national second place competitor to Tesla's charging network, but they are years behind in build out right now.
Depends where you are I suppose. In addition to Tesla's network, Europe has:
- Ionity: https://ionity.eu/
- FastNed: https://fastnedcharging.com/en/
- Allego: https://www.allego.eu/
- GIREVE: https://www.gireve.com/en/
And more. All standardized on CCS type 2 plugs which is another plus.