While this is definitely a problem when it happens to us individually, I have to say it's much more the exception than the norm. I just finished my trip where I hit 200 SuperChargers....
90% of the time I was the ONLY car, Tesla or otherwise
about 9% of the time there were a couple of other Teslas and no ICING
Maybe 2 times were SC's ICED and in both cases there were still plenty of open slots.
Only once, in CA of course, did I have to wait for an SC (about 15 minutes) but that was due to full Tesla usage.
One key is for Tesla to NOT take the prime spots...which in most cases they don't and this solves 95% of the ICING.