We currently don't intentionally block or disable third party clients or action the accounts of people who use them.
We do monitor the traffic of spammers and we build heuristics around how to identify them -- and sometimes third party clients get caught up in that. Cold comfort, I know, but it's not us trying to block/come after well-behaved third party clients.
Anyway, to OP, good luck with discordo! For one of our internal hack weeks a few years ago I tried to build an RFC1459 compliant Discord gateway... it was a fun POC, but definitely lots of rough edges because the paradigms don't exactly match up. :)