The other US networks are at the whim of both 3rd party hardware suppliers & 3rd party software vendors. So they are just integrators really, and do a very terrible job of it. They are slow to get new parts, slow to send out repair teams, etc.
Further a lot of them have screwed up incentives, such that the person charging is not really their end customer. Also they all lose money.
Some of this is the result of legal settlement mandated networks (EA) or them pre-selling some amount of charging to automakers (EA) or partnering with states (evGo) or running an ad network (Volta)..
All of which means you, the person charging, are not the customer. Whether you can successfully charge or not is besides the point, and possibly increases their losses if you do charge!
Yes I know Tesla also receives government money, but it is just one part of the funding, and they are actually performing well as a charging network, because they want to sell more cars. They must make enough money off it that they are willing to open it up to 3rd parties now.