That’s one of the big questions here: if repressive governments are in your threat model, does a given system mean a normal person is likely to leave too much data on their devices? It’s really easy to imagine checks on all of the phones seized from protesters, anyone suspected of spending beyond their reported income, etc. so something which doesn’t make it really easy to purge old history is pretty risky - not least because if they catch you hiring anything there’s a nasty problem of convincing them that there’s nothing more still hidden.