There are further questions on the reddit link.

   > - How often do the TLSA lookup errors happen at large organizations?

   It is a serious error that should be immediately fixed by all
   responsible parties.  Like the water not working.

   Your questions are both good and irritating.  They are important and
   rarely asked.

   The proper response in my universe is to find the technicians and
   groups responsible and inform them of the details until it is fixed.
   Usually started at normal points of contact for the organizations
   involved.  i.e. millenial hobby sysadmin culture.  Sometimes they offer
   you a job in the process.

   Data gathering is helpful too.

   Governments have historically needed help with technical things.  Dunno
   what the case is now.

   The domain name probably has a technical contact listed in its
   registration.