IMO a "standard" that isn't publicly available free of charge (like the laws) should have no legal standing (i.e. national bodies and laws should never defer to such standards or demand compliance). Otherwise it's just an opaque law that only the rich get to read.

Now if companies want to make gentleman's agreements to follow each others' paywalled standards.. by all means. But they don't get to complain if others violate these standards left and right.