Almost nobody has bought government bonds for a long time besides pension funds (due to obligations), banks (due to regulations), foreign governments (due to ForEx necessity), the Fed, and a pretty small amount (~8%) held in 401ks (overwhelmingly by older folks) [2].
Rich people certainly aren't buying Treasuries to protect their wealth - unless it's someone like DoubleLine betting on interest rates only going down and the forced greater fool (pension funds).
401k people are only buying treasuries because of the "age old wisdom" - not because it makes sense unless you think like DoubleLine that treasury yields - long term - are only going down.
[1] https://fred.stlouisfed.org/series/AAA10Y
[2] https://www.thebalancemoney.com/who-owns-the-u-s-national-de...