I don't understand what there is to not understand about the the farm team narrative... I think soccer fans in and around NYC that could be potential fans of this team are very, very aware of the CFG connection. I think that we on the forums are just those that were the most okay with it... obviously, because it's a self selecting group (and even more self-selecting as those who tire of the team/ownership drop out of the picture, it becomes an echo chamber). Yes, there are those folks who are EPL fans and just hate Man City, and wouldn't ever be a fan of NYCFC for that reason. But far more importantly, there are those fans who just can't stand the idea of rooting for a farm team / minor league squad. You know the usual arguments ... there are so many pro sports (and other entertainment) options, why root for a farm team... (Why NASL cared so much about D2 vs D1 designation... Americans don't want to watch minor leagues.)
With regard to MLS still being a growing league and now starting to become a selling league (a positive development)... I think that's really different from NYCFC being a feeder/farm team/proving ground for CFG. If you're an independent club in MLS with independent ownership, sure you're going to hope to develop guys and sell them on to leagues that are (currently) bigger and better than MLS, but you're no one's farm team... your team winning is your ownerships number one priority. And you may be selling guys now, but you're aspiration is for your club to grow and for the league to grow, and be the best in the world one day. That's a very different mentality than always being the little sister/brother club to the mothership.
I guess the simplest way I can put it is this... if I'm a Portland Timbers fan (for example), I know that that's my team, and I know who's in charge, and I know they want to win, and I know the actions they take are motivated by helping us win (sometimes in the short term, sometimes in the longer term) ... I'm a founding member of NYCFC and have been following them for half a decade now, and I literally cannot say any of those things about this team or ownership group with any confidence.