[ether_at_cpan]

Not really true? There are lots of validators supporting the most recent version: https://json-schema.org/tools?query=&sortBy=name&sortOrder=a...

[afiori]

I might be wrong but that list is mostly libraries I think?

I agree that it is easy to implement a recent version in your own code, what I meant is that a lot of the tools/software you might want to use JSON Schema with (eg mongodb validation) only support old versions