In any threat model where the attacker may gain physical access to servers, RAM interception is a concern. The original poster does care about physical access.

In any threat model where the attacker may gain physical access to servers, RAM interception is a concern. The original poster does care about physical access. I'll mention that unencrypted in-memory data is accessible in pure-software ways too (which usually require root) - debugging tools like GDB, VM snapshots, memory forensics tools, /proc/mem, etc. So unencrypted in-memory data is a problem too if root access (including both by infra-provider insiders and external attackers) is part of your threat model.