If someone starts announcing dozens of prefixes in v6 then they either
get blocked or they get a filter that restricts them to their covering
route (or blocks them if they don't have it).
Too late once they've announced them
As with v4 if the herd doesn't stay together on policy then once some
have accepted the rest get picked off one by one as their customers
complain (I've watched a smaller ISP try filtering v4, sucks to be
If there is to be a deaggregation limit it needs to be universal and
set up already so people don't try to annouce.
Doesn't work is a better argument than some will try and stop it
working. Game on.