Puh-leeze. The estate tax exemption for 2015 is $5.43M, actually higher for "family farms", aka agribusiness. It affects 0.12% of estates, none of them middle class in the slightest.
A variety of coping mechanisms are available to those who can afford lawyers to put it together, including Mitt's multimillion dollar IRA for his wife, trusts, gifts & so forth.
http://blogs.wsj.com/totalreturn/2014/10/30/estate-tax-exemption-for-2015-announced-by-irs/
The whole argument puts the lie to Righties' mock piety for hard work & exceptionalism, not to mention their ravings about free shit for anybody not their economic equal or superior.
If inheritance isn't free shit, what is?