there was alot more of it when PN and TW were around. the most Senior people used to fly the longest flights and for TW that meant TLV or RYD, PN changed when they sold the TPACs to UA

Now most Carriers except say US have several flights in the double digits 10+ hrs, so Id think they would vary their flights. US has only TLV so Id think their most Senior people would want to keep on that 1

Most European Carriers dont have the Bidding process and allow their crews to bid once or twice a yr for a particuliar routing

Also most Carriers want someone who speaks the language of the Destination on board so that helps keep certain crew members flying only certain Routes. Hebrew speakers for TLV, Chinese for HKG,PVG,PEK, Japanese for NRT , French for CDG etc etc