[konsalexee]

I think the title is stating this: "Postgres LISTEN/NOTIFY does not scale"

That means for moderate cases you do not even have to care about this. 99% of PostgreSQL instances out there are not big "scale".

As a sr. engineer is your responsibility to make a decision if you will build for "scale" from day zero or ignore this as you are mindful that this will not affect you until a certain point.