Yeah, this is completely ridiculous.
It has nothing to do with technical specifications or limitations, it has everything to do with development priority, driven by revenue. There isn't a revenue incentive for EA to spend the development time building in a Pro Bowl. Yet, there is the revenue incentive for EA to make an Ultimate Feast Turkey MUT card
There's nothing technical preventing anything, it's about revenue priority. For Madden NFL Football, turkey-based trading cards are a higher revenue priority than accurately portraying an NFL season.