I got some inexpensive Aliexpress 24-spoke road wheels for my gravel bike, and on a ride a couple of weeks back, pulled a goathead thorn out of the front 28mm tire about 7 miles from home. It didn't seem to be leaking, but was half deflated the next day. I swapped out the tpu tube for a new one, and thought I would have trouble finding the hole, but it was quite easy to find after adding a little air. Those size holes in a butyl tube would have it too flat to ride much faster than that, at least in my experience.
A couple of days ago, I again saw and pulled another thorn out of the front tire on a 42 mile ride. I got about another ten miles before I reached a nice park where the tire became too flat to continue. I had spare tubes, but decided to try and patch the hole on the road with the included cleaning swab and glueless patch that came with the tube, which I had never tried before away from home. Again, the hole was easy to find, and that patch is holding up as of today.
About the 30 mile mark, I noticed the back tire getting mushy, and found just the pointy part of a thorn embedded in the tire. After removing that, I pulled out just a section of the tube from the tire, and again put a glueless patch on the easily visible hole. It's still holding up at 90PSI as of today, too. I know that others have written that those type of patches are doomed to fail in a week or so, so I'll post here if they do, or in a couple weeks, whatever comes first. And try to put some more miles on those tires.
Based on my massive sample size of two punctures in the front which seemed to leak very slowly after the thorn was removed, maybe the high pressure smushes and almost seals the tube against the inner part of the tire, as compared to a butyl tube. The back went flat quickly because the thorn part broke off in the tire and was holding the hole open. If they fail, I will try some Gorilla Glue under the patch, or that in conjunction with some 3M Blenderm tape at home when it can cure overnight, which I have seen recommended on R*dd**t.