"Abuse" of SRQ sounds like a ludicrous argument. In other parks, Phantasialand as an example I know, one can't abuse them: the SRQ is blocked initially, and ride operators let the others enter first, then open the SRQ to place single riders in the remaining, empty seats. If a group enters SRQ and wants to ride together: bad luck, ride alone or get back to the regular queue (the end, not in front)! Didn't they do the same at AT?
In addition, they use SRQ to mitigate the offensive class hierarchy of parallel regular and quick pass queues a bit, by opening the priority queue for single riders (quick pass push in front later).
To me, it sounds more like removing SRQ is part of a strategy to aggressively push fast track "upgrades", Port Aventura style. Which includes letting rides operate partially empty, while queues are building up.