Taking a typical track, a dev might start working at 22 and start a family around 30, leaving 8 years to save 300k (20% down payment on 1.5M), meaning they have to save $37.5k/year. Add to that a $2-3k/mo rent for those 8 years, and you basically double that. Including income tax, that's about $110k/yr just towards housing. Let's say they have $500-1k/mo of other expenses (food, gym, discretionary) and add the $5.5k annual IRA contribution, and that's ballpark $130k/year average every year. That's without a lot of the fun things you should do in your twenties and an irresponsibly low contribution to retirement.

Oh, and with the other 80% as a loan, there's a requirement that the payments aren't over 40% of your income, so a $1.2M loan at 3.92% for 30 years means you need to make more than $170k/year. You're right that lots of good software devs make that, but this is a crazy amount above the area median. And that's the lowest end $1.5M from the $1.5-3M range for a 3br in those areas. Hyperbole is not quite the way to spin it.

As we had some posts about salaries in google there was information about stock options and they usually exceed 300k in 4 years. You can make such initial payments only by selling your google's stock.