I am joking, of course, but I think you're completely right in that for beginners, a small investment in upgrades (or even just a good solid bike) pays for itself in huge boosts of performance.
Of course, after that, then buying more and better things is just bad for your wallet ;)
When I finally got on a "real" bike, I flew. I was much faster and agile than my bike-riding friends. Because I couldn't upgrade the bike, I had to upgrade myself, and these investments are compatible with any kind of bike (or sport, actually).
What was surprising that pro on lady's bike couldn't match layman journalist on proper road bike. Basically all the energy spent on women's bike goes to flexing (heating) the frame. City bike built like tank was better as at least it was sturdy.
However it also shows that good bike is so much more important as you would think pro would match you riding anything with two wheels.
Also curious about all the people who say "no surprise considering the bike".