Pre-shared keys, as they suggest there, have no forward secrecy - which makes them great for those who really like stealing, say, IPsec keys… like the NSA. It may work with the kind of old military key infrastructure they and GCHQ have, that regularly distributes random keys from centralised, organisationally-trusted sources on specialised hardware; it is a terrible recommendation for civilians.
Interesting that they're still married to P-384 (probably the most annoying curve to implement correctly). Properly-implemented Ed448-Goldilocks is safer, and that's what CFRG are going with for the "paranoid" level.