It's probably likely that some stars would appear most often, seem to "hog" the airtime, but in my favourite TV shows that are an ensemble cast, there doesn't seem to be any one actor taking top billing for number of minutes on the air, and I think that's where soaps make a terrible mistake.
But I've given up analysing these dratted soaps. In my jaded and predictable opinion, if Trevor St. John were to be relegated to the same status as, say, Nigel, OLTL might have done better in the ratings. JMHO.