To be fair, that's also true of RFCs as. (E.g., IP over carrier pigeon). But that doesn't really matter.

Take HTTP for example. The is no ISO standard, just a smattering of overlapping RFCs over the years with weird spellings (Referer) and ambiguities (GET request entity).

And the entire web is based on HTTP.

The quality of the "specification" documents is not high, nor very official, but it's the best we have, so people treat it as if it were.