Yup what he is looking for existed, maybe, 20 years ago. Maybe. Even then like you say inflation always takes "it's cut" first.Just for clarification. The guy said he wanted to "park". So, he wants a near cash alternative.
There is no way anyone will make a positive real yield risk free. No way. This gives him a fighting chance to come out with an absolute/nominal positive yield much higher than standard treasuries.
In cash, he will loose by the inflation print. In VTIP, his REAL loss is locked into about 2.5% currently.
In order to beat inflation the return has to be greater by "X".