It won't, and it doesn't. You're misinformed on this topic.
There's a blanket exemption for estates up to $5,000,000: http://www.irs.gov/Businesses/Small-Businesses-&-Self-Employ...
Nobody is interested in taxing your kid's college fund--we just don't want the Waltons running our country for the next 100 years: http://walmart1percent.org/family/
http://www.theguardian.com/money/2014/jun/03/uk-average-hous...
The tax is apparently 40%. So the heirs of a single person with a home worth twice the average will owe £11,600 in taxes (it looks like some of the exemption is transferable for couples, so ~0 taxes for lots of people).
It doesn't seem so onerous for people receiving a $600,000 house to have to pay $20,000 in taxes (it's certainly an amount that most owners of such houses will be able to plan for).
It's not a case for totally eliminating estate taxes.
The point is that people should stand on their own two feet, and not coast through life on daddy's money (or government largesse, for that matter).