Bookworm,
You and I probably know several people who are not pilots and not even students who can fly the aircraft on instruments in IMC.
However, the law is very black and white and according to the law the only person who can fly an aircraft in IMC is the holder of a valid IMC or IR rating.
That is the legal position. To have it otherwise would legitimise basic PPLs flying through cloud.
From a legal point of view therefore, unless the safety pilot is qualified they according to the law are not capable of performing the actions that may be required of them.
If you were to go down the road of not needing to be qualified for the conditions, where do you draw the line? Is you passenger good enough to keep an eye on you because you are not current?
Regards,
DFC