I wouldn't use steel wool no matter how fine it is--it'll leave fine scratches and swirls...they sell some made of copper some body shops used to remove overspray but I'd stick with cleaners and only use any abrasives as a last resort...toothpaste is about as coarse an abrasive you should use,if any..
I've tried waxing windows and it does make snow removal easier,but the wiper blades did not like the wax,they would smear,skip and chatter with wax on the windshield..there is a "glass wax" sold in grocery stores for things like ovens ,I never tried it on my vehicles,but it does make food less likely to stick...
Some vehicles have a plastic coating on the inside of the windshields--I recall selling plastic single edge razor blades ,some inspection garages ruined windshields when they used the old steel razor blades !.