I stripped a vintage AMT Indy car in DOT 3, pulled it out after a day, and it literally crumbled.
I've also stripped an automotive-grade catalyzed urethane clear from an old Revell Chevy panel delivery with no adverse effects whatsoever...and the DOT 3 was the only thing that would even slightly soften the paint...but I still had to carefully scrape it with an X-Acto chisel-tip blade.
In my experience, high-proof iso usually strips factory finishes on cars and model railroad equipment...and some lacquers.
Oven cleaner takes off old enamels, usually, even stuff that's been on a model for 30+ years, but often takes several applications on the really old finishes.
I'll only use brake fluid as a last resort.