Presumably they are not going to remove the workarounds until the software has actually had a chance to disseminate? For example the resolvers they list are all new releases and aren't in any current Linux distro. Which means they are saying that in a couple weeks all Linux resolvers could stop resolving some domains unless they adopt an unsupported release of the resolver?

They don't list it, but presumably the same applies to the Authoritative servers. I run a pretty vanilla NSD install and it fails several tests. NLNETLABS (the authors/maintainers of nsd/unbound) is listed as a supporter, but they don't mention anything about this on their site nor does their documentation mention anything about settings to control these features.

If this will actually have the consequences they describe it was terribly mismanaged.