Still lots of them is use, as well as lots of nob and tube wiring, and old ungrounded 2 wire systems
I remember a home inspector saying a fuse box is actually safer than breakers IF everything is sized right...But once someone put a bigger fuse in, all bets are off.
Makers sense....a breaker is a spring loaded device that can fail. Many a house has burned down due to breakers not turning off.
Damn, I got hit with 220 once as a 16 year old kid, working at a Days Inn. I was changing an AC unit that was hard wired in. I shut the breaker off, but didn't use a tester, and got zapped bigtime. The breaker was labeled wrong!! Never again!!