Since the east's attrition & that coveted left seat is so important (vs. $$$, contract improvements & time off), why would someone bypass the chance to upgrade in any aircraft?
This is one of the more frustrating themes from the west and I'm surprised you have fallen into it, since you are one of the more level headed posters.
If you look at out seniority list it is easy to see that coveted left seat is not always coveted. Most pilots want to make the most money, with the best QOL, no matter what seat you are in. It's not a simple right seat to left seat over here like it is on the west, it's multilayer and often a F/O block holder seat will provide you with better money and QOL than bottom reserve captain. It depends on a lot of things. I live in base and choose to bid reserve captain, but I would rather fly right seat on the 330 or 76I than commute to it. But we have options.
I'm guessing this type of b.s. gets thrown around on your boards so much that you guys begin to believe it as fact.