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.