How do I change a persons render settings through a script? I've looked in the render settings service but I'm not sure what property to change since most of them don't have a description on the wiki.
You don't
People would not be pleased if you made their potato overheat
What you can do as an alternative is to have some internal game graphics settings which cull a few effects locally as well as get rid of some detail geometry and mess with lighting a little.