That's an underrated suggestion! However, even if configured as a single-hop service Tor would add substantial latency and bandwidth restrictions, and would not

That's an underrated suggestion! However, even if configured as a single-hop service Tor would add substantial latency and bandwidth restrictions, and would not support UDP. But Tor would not require the user to self-host external infrastructure so could be used in a pinch where this (or more canonical ssh -R) couldn't.