The left hand doesn't know what the right hand is doing.

Routes get changed, stops get changed, landmarks disappear and they have no means of communicating this.

In recent years, they had a stop at Dublin Airport called "Arrivals Terminal" and I was thinking "Fools, they mean Arrivals Level / Arrivals Road".

Nope, they were referring to the 1950's-built North Terminal: https://www.openstreetmap.org/way/26481951 that used to be used for arrivals (the Old Central Terminal Building being used for departures) - until the 1970s when Terminal 1 was built. Until a few years ago, it was used as the Garda Station.