Estate tax is when someone dies and another receives an inheritance. The situation the article describes is where adult children are being subsidized by gifts from their parents, which is not in any way illegal, and is subject to gift tax, not estate tax.
The annual gift tax exclusion in the US, tax-free, is currently $19,000.
The lifetime gift tax exclusion, tax-free, is ~14 million dollars. So if a parent bought a $13M NYC condo for their child, it may functionally be tax-free.
There is no law in the US which parents cannot purchase property for their children but retain ownership in that property (until their death, in which case it could be transferred to the children).
As someone who has successfully purchased properties in major metro areas as a couple without the assistance of any relatives or non-conventional loans, it's a tough one. I do agree that parental gifts need to be taxed harder.
I've experienced the opposite of what's described here, where people truly can't believe that we've purchased our homes without the use of gifts from relatives or some other windfall. When we closed on our first house, I turned to my wife and literally said "how do normal people actually do this?"
