That has no relation to the cases above which were of people running Tor exit nodes from their home. If one wants to hide their Tor usage then that's something else and there are pluggable transports that are already built-in the Tor Browser to obfuscate Tor traffic to look like something else--no need for a VPN.

How does this affect exit nodes?

If you're worried that law enforcement will knock on your door because somebody used your exit node for illegal internet activity, a VPN service (that does not log traffic) will give you additional protection by exposing their IP address, not yours.

A lot of VPN services forbid running exit nodes in their ToS as it tends to trash IP reputation...