What's ultra-rich? This claim isn't saying much unless you quantify it.

I don't know, a billion dollars?

Intuitively, I find both your claims - that most people only try to match their parents' tier, and that it's easy to become ultra-rich if you focus on it - to be wrong, but it'd be interesting to see more arguments or evidence in their favor.

A quick Googling turns up a few papers which suggest that parental expectations largely define a child's level of educational and financial achievement. On a more intuitive level, I can only point out that the clear majority of Americans either don't go to college because their financial ambitions are satisfied by blue collar work, or they go to college in pursuit of a degree with a clear Middle Class career path attached to it. Do you know anybody whose stated goal is to be wealthy, rather than to be a doctor or an engineer or some specific career? I don't.