MX. there's the diference. GFCI's were nOT accepted, and faced tremendous opposition, for nearly 20 years. Even once the technical "bugs" were worked out, there were numerous 'human engineering' issues to be dealt with, before they could reliably wired correctly.
Indeed, the latest "fix" for mis-wiring only took effect last month!
Adoption of GFCI's was slow, and the application was quite limited, until the thing was prooven in the field.
How great was the resistance to GFCI's? I remember the inventor touring the country, placing his young daughter into a tub of water, and dropping a toaster in- to proov the things worked! (And this guy surrendered his patent, and nad no profit to make!)
The opposite has happened with the AFCI. A fancy new invention is assumed to be a great idea, then mandated for use everywhere.
