That is actually why I mentioned the 1st and 70th percentile bit - it told me that the potential was there. Back when I arrived, if I got 2x my salary (the exchange rate was much lower then) for Houston, there wouldn't be much head room for increases. Over here, if you do "ok" at your job, your yearly increase will be 0-2% once you've plateaued, and people are fine with that since prices don't tick up continuously. Plateuing is something that exists, but is hidden in SA due to inflation.
Anyway, point being that even in what ostensibly looks like a cheaper area, allowing you to buy a nice house up front, the low interest acts as a double edge sword, meaning that the costs of your property don't diminish over time like they do in SA, and for the same reason, your income is likely to grow much slower (unless you're being underpaid to start with, then it will grow quickly and then converge). This means that many would buy a much cheaper house than one they could "afford", because it eats into savings and any future budgets for a long long time.
Austin is a great city. Many of my colleagues have worked in Silicon Valley, and then moved to Austin once they had driven up their salaries high enough (very few companies expect new hires or transfers to take much of a cut, if at all for moving to a cheaper area). Living on $150-200k in Austin is amazing, while in SV it only affords a middle class lifestyle.