I'll be odd man out.
Nothing. Yep, nothing.
I carry a compressor in my TT and I have no idea why? In 35 years I have never used it.
Looking back, I have no reason to use it? I fill my tires up to max pressure (sometimes 10 over max) and go on vacation for 2 or 3 weeks. If my tires lose pressure over 2 or 3 weeks I have a problem with the tire and I fix the problem.
If I have a low or flat tire I change to the spare tire and go on my way to a tire shop to fix the tire that has a hole in it. After it's fixed I put it on as a spare and go on my way.
I have no reason to carry a compressor and I can't see why anybody else would either.
(Oh I guess if I was out in the desert a lot I might carry a plug kit and a compressor; but that's about it. General roads on vacation; nope don't need it.)