I think Abu Dhabi was only served as an intermediate stop on flights to Europe. Hence you'd have seen their 747-200's there. With the advent of the MD11 (now gone) and B747-400 Garuda flies nostop to Europe (Singapore-Frankfurt, Bangkok-London).
I recall flying Australia - Abu Dhabi (PER-DPS-BKK-AUH) in 1995 (I think). The B742 into Abu Dhabi was full ... when I got to immigration and baggage claim, I was the only one there! The flight went on to Paris I think. Flew back on SQ (AUH-CMB-SIN-PER), and now both have stopped flying into AUH.
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