Now correct if I'm wrong but if the highest medal is gold then you do not get points for using safety systems but it the highest medal is platinum then you get points for using safety systems.
This is basically true. There are some instances where the game suggests a platinum medal is possible, but because of bugs it is not, even if you use safety systems.
IIRC both platinum medals and getting points for using safety systems were introduced in TSW4, so basically yes.
I never get anything but platinum medals, unless I'm playing an old route or the training centre then it's only golds maximum, I always use full safety systems even on DE routes though.
Sharing this from our TSW4 announcement article, it breaks down the expected scores needed for the 4 tiers of medal: If you see any services which should be awarding platinum medals where you'd expect, please flag them to us, and we try to sweep through these when we release new patches
