I've pointed out elsewhere that the truck or suv is but one segment of the transportation system we are contemplating buying. The other two are the fueling segment and the support segment. Elon Musk was smart enough to understand this and, initially at least, put a lot into these other two segments. His fueling segment is still great but his support segment is a bit lacking at this point. RJ Scaringe is also a bright guy and I am sure he is as concerned about the other two segments as well. The big difference between the Tesla System and the Rivian System is that the former is a general use transportation system which means that most users will be using it to get to and from work, the supermarket, the kids' school etc. and given that most charging will be done at home. Tesla users go on longer trips, of course, and hence the SC network.
The Rivian system, by contrast, is intended to be one in which the user goes to remote places, though, of course, there will be lots of taking the kids to scholl done with it too. Thus the Rivian fueling segment is even more important than is Teslas.
I guess the ultimate reflection is that the Tesla community got by when the Tesla SC's were few and far between and so the Rivian community will doubtless be able to do so too. Kona drivers and Leaf drivers get around. Tesla owners drive out the Gaspe and around the Maritimes where there are no Tesla SC's.
The number of Other SCs actually exceeds the number of Tesla SC's and it is expanding. But it does not seem to be expanding as logically as the Tesla system. For the Rivian user that's not necessarily a bad thing as, presumably, Rivian drivers will venture into the less traveled places than Tesla and Leaf drivers.
Most of the existing stations seem to be able to accommodate only one car at a time. In many places that's not a problem. There isn't, apparently, huge demand for the EVGo charger in Bennington, VT nor for the CircuitElectrique one in Stornoway, QC. The newer ones (EA) are located in more populated places and seem to have more stalls so this problem is improving where it counts. Reliability and availability are concerns. The current "network" isn't really a network in that there are multiple operators and in some cases the operator is the gas station or convenience store that installs the station. So lots of "didn't work" or "wouldn't charge until I got the company on the line after holding for 20 minutes" stories are to be found on plug share. But they seem to be fewer than previously. The EA network is, of course, a network but I have seen reports of people arriving at a station with 10 stalls and seven of them are out of service. So let's keep in mind that EA is a new network. We'll hope that the bugs get worked out but that is no guarantee that they will.
The rates charged by the Other suppliers seem, to a Tesla owner, outrageous often amounting to $0.50 kW/h or thereabout. I understand that this may look like a good deal to a California or Hawaii resident but are a shock to much of the rest of the country. At such rates the cost of "fuel" in little or no better than the cost of fuel for an ICE vehicle.
I'm a Tesla owner and am, as such, spoiled. As I noted earlier, there are lots of other EV's on the road and there owners get by somehow. Someone who has just taken delivery on an RIT or RIA is no worse off than someone who has just taken delivery on a Jaguar iPace or a Hyundai Kona. To get an idea of what such folk deal with search for road trip reports for a vehicle type (e.g.
https://insideevs.com/news/355375/video-hyundai-kona-electric-us-road-trip/ and
). Doesn't look that bad from these. And it looks as if the first of these is where I got the 7 out of 10 report.
All such concerns go away on the day Scaringe and Musk sign an agreement to let Rivian owners use the Tesla network but don't hold your breath on that.