Disclaimer - I am NOT advocating for Open-Only, I'm just making an observation.
Today I decided to join the Tritium Truckers, in hopes to make some meager credits to help me slowly progress to my goal of someday owning a fleet carrier. The best prices were between two outposts, so I configured my Python for cargo running and started my trucking - in a private group. Was I worried about gankers? A little, but not terribly so. No, what I wanted to avoid was an insane line of CMDRs all competing for that one medium pad. And that's when it dawned on me - everyone lining up for a great deal is realistic, and I'm basically "cheating" (figuratively, not literally) by creating my own parallel universe Walmart on Black Friday where there are no lines.
If the game was Open-only, these lines would force players to spread out and accept less than the perfect exchange rates in trade, thus bringing balance to the game. It would also bring legitimate PvP piracy (something I enjoy), and yes, ganking, which would also balance the game. I'm not saying it's a perfect solution, heck it's not a solution at all (modes are here to stay), but I do think that a large contributor to the success of all these gold rushes is that we can create our own private realities where we don't have to deal with long lines, criminals, and other realistic challenges. And because of this, I do think the game is less than what it could be.
And yet, here I am trading in the safety of a PG / Solo, so I guess I want a FC more than I want realism at the moment, LOL.
EDIT - I just found a route between two large stations, but the theory still applies I believe. Just consider some of the traffic jams we used to see during community goals.