I'm sure wherever these reviewers are doing their reviews, they're getting bad experiences. But personally I've never once had a problem. Maybe bad maintenance is more of a localized thing?
Think of it this way: The Supercharger network has to be reliable, because there's only one station every ~100 miles or so. The CCS network can afford to be a bit less reliable because it's more redundant. And even then, the "less reliable" typically means that one out of four available chargers in a location is out of service, not that the location itself is unusable.
And there are apps that lets you see the status of chargers at a location, so you can check in advance whether a particular location is working. If a location seems to be in poor repair, you can always plan around it.