The edit window closed for the original post. Here are a couple more thoughts:

Fedimint, as it is currently being built and explained seems to be mostly advocating for many small mints versus few large mints. Of course there is no technical reason why a mint needs to limit its size, but there may be some good social/economic reasons for doing so.

Nevertheless, it does seem reasonable to think that there will be some mints which will be created solely to serve (the federations of) other, perhaps smaller, mints.