That appears to be the case. Almost all of these sites were in Ohio, although there were a couple in IN and KY. It appears that EVgo is pulling out of Walmart (and Sam's Club) in that area. There were some comments in Plugshare indicating that local EVgo subscribers received e-mails that EVgo would be decommissioning those sites on Feb 21, and that certainly appears to be the case. No other information was given, and the sites were pulled from EVgo, AFDC, and even the Plugshare entries have been removed.
Perhaps the affected Walmarts will be partnering with Electrify America to put in more robust sites, although I don't see anything on the Electrify America coming soon map to indicate that (doesn't mean it won't happen, but they are surely not advertising it).
Or, maybe they are just doing a system upgrade of those sites and they will be back at some point. I don't have any good information related to this, but perhaps a local does.