I agree. It generally polices itself. Most ICEing at superchargers is at locations that are not busy. When it gets busy, like even half full, the ICE drivers are much less likely to try to squeeze in between the charging Teslas. And if they do, I would imagine many Tesla owners have a talk with them.
The one scenario where ICEing concerns me the most is at small hotel superchargers late at night. Ellensburg with only 5 stalls used to have these problems, but I think they have been enforcing it pretty well for the last couple years. The Dalles is another one where this is a concern but last time I was there, it was around midnight and all stalls were open despite the lot being crowded. Albert Lea, MN used to be the worst for this, but thankfully they just built a new supercharger at a truck stop on the other side of town. Gallup, NM is another one to look out for.