Without SSL on the LAN side of a reverse proxy, I presume that all traffic between the server and the reverse proxy is unencrypted and, thus, accessible to any device on the LAN.
Which specific scenarios result in this being a concern? The primary concern that I can come up with is if you know that there are untrustworthy entities connected to the LAN (untrustworthy devices, or perhaps malicious individuals).
Its worth considering to do SNI routing without decryption in the reverse-proxy, but usually it is not a major issue to just terminate.
Can you link an example on how that can be done?
https://levelup.gitconnected.com/multiplex-tls-traffic-with-sni-routing-ece1e4e43e56