I'm an electrical contractor. I don't know of any "federal laws" about breakers. Electrical installations are generally governed by the local city or county building department. Usually they inspect according to the National Electric Code. This is not a federal code but just the name of the code. Adopting it is voluntary and usually done on the state level.
At any rate, there have been no changes to make breakers trip "easier". A 30 amp breaker is supposed to trip when more than 30 amps flows thru it. Time will always be a factor here. 31 amps might not trip it for several hours while 100 amps should trip it really quick. This is more a function of the breaker's design and varies among manufacturers a bit.
I suppose it's possible he might have had Federal Pacific breakers before and now has something else installed. Federal Pacific breakers were very popular in the 70's and 80's until it was discovered they were faking the UL listing and printing their own labels. They got sued and went bankrupt. Their breakers sometimes didn't trip at all. If he used to have those and now has good breakers that might explain his comment.
