The inspection will likely be similar to state car inspections. Costly and not much value. Example: If there are four chargers and only one is working, that's still counts as up.
So, it has to do with regulatory capture.
On the one hand: Take gas stations' actual fuel pumps. There's pretty much always a weights-and-measures sticker on them saying that a Gallon is a Gallon.. and said sticker is usually up to date, too.
Every so often a gas station owner gets caught with their hands in the cookie jar and gets bitch-slapped by the courts, occasionally going out of business as a result.
And if it turned out that a weights-and-measures inspector was being paid to look the other way, people would get pissed, rightly.
An attempt by, say, oil companies to negate penalties and loosen the requirements would be met with derision.
On the other hand: Look at your telephone/cable/what-have-you bill, where all sorts of "fees" are slapped in there that are, simply, the cost of doing business for the company, are arbitrary in nature (as in, with no oversight whatsoever as to the truthfulness of the amounts of those fees), and are, effectively, cheating consumers. How the heck these companies even get away with
any of this mystifies the heck out of me. But, normally, it's because government regulatory agencies who are charged with regulating this kind of behavior are clearly either on the take, beholden to political interests that are being bribed by donations (the same thing, really), or are crooked.
Heck, just look at the Shortsellers Enrichment Commission!
So, will the up-time requirements in the ERA be met? At least with the individual states regulating the up-time requirements, it'll give the charging companies fifty moving targets to hit. Not that sufficiently endowed companies don't try for that (see: Telephone/internet last-mile companies of every stripe), but it'll at least make the charging companies lives more difficult.
The biggest danger I see in all of this is if some cock-a-mamie company drags some state regulator into court, claiming that the ERA enforcement of the up-time standards is unconstitutional. (See: DMCA notices, where the people sending the notices pinky-swear that they have, indeed, checked for copyright infringement, where the courts have somehow ruled that if they get it wrong, they can be sued for perjury.) A Federal Court's ruling can then ruin it for everybody. Unfortunately, sometimes a crooked plaintiff can just claim, "But, Judge, It's Just Too Hard!" and get away with it.