i'd be fine with letting them keep some of their personal (non-stock, non-private, just liquid) material wealth in exchange for being legally barred from any participation in politics, with a team dedicated to keeping an eye on their financial activity (effectively sanctioning them outside of personal purchases)

it goes with them when they die, their kids can have their personal physical property (good luck maintaining it all)

let them live out as voiceless, comfortable relics of the past, helpless to effect anything outside their own (ever shrinking) personal circle. maybe grow as humans or become isolated and unhinged, gawked at by comrades hoping to glimpse them through the curtains in darkened rooms