Heck, here in the Northeast one hundred year old plus houses still have 60 and 100 amp service with knob and tube, push button switches, fuses, and ungrounded.
My house was built in the late 1950’s. ungrounded wire (I’ve replaced some of it) 100 amp service (Breakers)
The oddest part is that the main breaker box is in an upstairs utility room. When I moved in there were only two breakers.
In the basement is a weird array of smaller boxes, some with fuses, some breakers. It’s mainly for the big stuff (dryer, furnace etc)
Even my neighbor, a master electrician can’t figure out why.