In other words, what happened to the old IETF that would have said
"Site local addresses are utterly stupid and wrong; how large a
block did you say you wanted?"
It went away with the old Internet that was mostly an experiment and research
tool used by a relatively small, elite group with largely common interests,
and a fairly high overall clue level (as compared to today), to support a
relatively small set of apps.
If some outfit decides it must have site
local addresses for any notion of the phrase, it will get them.
well, if they expect apps to actually work with those things, they're
seriously deluded. and no amount of money will stop the tide.
Why won't existing uses of site local addresses be grandfathered?
people can be deluded if they want to. vendors can encourage those delusions,
and try to sell them products based on those delusions. the question is
only whether IETF should lend support to those delusions.