Looking at it objectively, it would seem to me that seniority must push down T&Cs for pilots. If people felt able to pick up and transfer to another, better paying, airline then surely there would be more pressure on airlines to offer competitive pay. As it is, most of us are trapped in our current roles and subjected to the all encompassing zero costs mindset that pervades this industry. Many copilots in my outfit are more than qualified for Command but stay where they are because the seniority system has trapped them.
We consider ourselves to be professionals and often compare ourselves to Doctors, Lawyers etc. I can't think of any profession where they have a seniority system. A Doctor doesn't change hospital to start out as a junior houseman all over again, because that would be ludicrous. The system we have is a hangover from the military (and even they have adopted a relative meritocracy these days) and it would be better for us if it went. After all, there's a reason that airlines hang on to Seniority these days: it isn't because it benefits pilots...