-fwrapv is there for people to use. People don't use it. Yes defaults matter, but they matter both ways. People benchmark with the default options and a comp

-fwrapv is there for people to use. People don't use it. Yes defaults matter, but they matter both ways. People benchmark with the default options and a compiler with -fwrapv turned on by default will lose those benchmarks and the "ordinary workaday programmers" still end up with trading correctness for speed, since one person at their workplace ran one benchmark once and picked the compiler that won in speed.