This just isn't true. As someone who is level 12 and has occasionally been in the top 100 in all three categories, I probably only get double harvesters in about 25% or less of my games. You do need to be aggressive though. There are lots of good builds for early aggression but I would suggest barracks -> rockets/lasers -> first harvester. Or perhaps war factory -> pitbull/bike -> harvester.
Anyone who goes double harvester immediately should lose a harvester to you which gives you more than enough money to keep up. Plus, having one less harvester means one less unit, which means you can produce faster.
(Also EA, this is an example of what I mean when I say that the inherent 'unfairness' of the game obscures whether loses are from player choices or level/unit imbalance which leads to frustration and anger. Players should be compensated when given unfair match ups and probably all losses in general.)