I've won this game in past years using only green pax, before I discovered the blue pax strategy. There's an old post from me called "How to win at AE" or something like that, in which I explain how to win as best I knew then.
Winning without superhubbing is extremely simple. Most people who play this game - most people - have limited geographical knowledge, limited imagination, and bad analytical skills. They tend to pile on the routes to/from cities they've heard of and ignore extremely large - though secondary - cities in foreign countries (i.e. most of the world unless you're a third-culture kid).
What's more, the game vastly overstates secondary-secondary demand while vastly understating primary-primary demand. This is in some way because of the absence of real connecting flows. LHR-NYC, for example, sees ~10,000 seats daily in real life. It orders of magnitude larger than would be a route like LHR-IND. Yet in this game the differential is nowhere near as big.
Yet despite all that, players still want to pile on LHR-NYC and ignore markets like IND-VCE, which are far bigger in this game than in real life.
Players also ignore the price breaks at certain distances (99, 199, 299, 399, 1499, 2999, 5999, 8999mi). Anyone flying a 6,050mi route early in the game is a dullard, yet I see that all the time because at each end of the route are two cities the dullard has heard of.
I could go on... Just know that I set the old pre-blue pax record in O1 years ago.