Why hasn't 128 bit been introduced yet? - eviltoast

x86 came out 1978,

21 years after, x64 came out 1999

we are three years overdue for a shift, and I don’t mean to arm. Is there just no point to it? 128 bit computing is a thing and has been in the talks since 1976 according to Wikipedia. Why hasn’t it been widely adopted by now?