The ability to pay $1M gets easier with age for a number of reasons and yes inheritance is one. Typical $1M buyers are not on salaries they own businesses, they become partners in law firms and medical practices who have paid off the large professional school loans. They save money over time and accumulate wealth they can use. They sell businesses they started and retire young. Lots of people save money, you seem to continously apply the agreggate average to the individual
Lastly some are on salaries and while salaries are stagnant for most they arent stagnant for everyone. No matter how bad things may be there is always someone who is getting a raise and that is who is out shopping for $1M home.
The greatest irony of all is you ended your post with an argument you typically use against others as your favorite attack. You said it’s different this time. LOL