Is there a permanent (non-emergency) patch/boot for a tire, NOT for a tube? I have a discontinued tire with a tiny hole in the sidewall. I’d rather keep/use the tire if possible. I’m very familiar with emergency tire boots, but those are for emergencies. I’ve left them on slightly larger holes, and found they wear through, not necessarily just from abrasion of the road, but just from constant flex inherent with a tire. I’m looking for a more permanent patch for the inside of my tire, and NOT the tube. I searched and could not find anything.

The hole is in the fabric of the tire, and causes a slight bulge with an outside radius no larger than that of a pencil.

Is there such a product in existence?
It is not clear from your answer if "tiny hole" means your tubeless sealant has a problem sealing it or that your inner tube is bulging through.

If the hole is really tiny, you can patch it with a tube patch. There are also dedicated tubeless tyre patches that are the same, but bigger and thicker. If the hole is really "tiny", they should work. If not, they could bulge through as well.

If the hole is bigger it can be sewn together. That can be then covered with a patch from the inside and with a polyurethane glue from the outside.


                
            

Only you can assess how dangerous that particular hole is and non-emergency such a repair can be. The higher pressures you use the worse it could be. Thin road tyres with 100 PSI and thick MTB tyres with 20 PSI are something completely different.