The missing bit though is that those 401ks are taxed later than now. A politician who wants to pay for their policy (good) but doesn't want to raise taxes (bad)

The missing bit though is that those 401ks are taxed later than now. A politician who wants to pay for their policy (good) but doesn't want to raise taxes (bad) can just move the timings of that tax bill to juice the books. Its been proposed in the past, along with the implications of changing the RMDs to boost government income.