LISTEN/NOTIFY is not brittle, we use it for millions of events per day.

I agree! It should be very stable, IMO. If not, then please send a bug report and we'll look into it. Also, now it scales well with the number of listening connections (given clients listen on unique channel names): https://git.postgresql.org/gitweb/?p=postgresql.git;a=commit...

The LISTEN/NOTIFY feature really just doesn’t get enough PR. It is perfectly suitable for production workloads yet people still want to reach for more complicated solutions they don’t need.

It's not the feature itself, it's how/what the llm tries to use it for. It uses it to cross any and all architectural boundaries.