Tesla's most recent version of FSD (which is released to a limited number of non-employee testers so far) uses only eye tracking for driver monitoring and does not require the user to touch the steering wheel as long as they are looking forward.
For Tesla yes, because it can't be trusted. Allowing you to not touch the wheel while still expecting you to jump in at any time isn't an improvement by any measure.
Any remote watcher can't be expected to avoid a crash in realtime.
Waymo is trusted to behave safely without supervision, but of course they monitor everything to validate and improve.