For new house wiring ? Probably not now. At one time house wiring was bare - it had no continuous insulation and was strung individually on glass-like support posts. That system had a name which I cannot remember. Some may be yet by existing today if the residence has not been inspected. Then wires were individually insulated with paper or cloth wrap which will deterrioriate . Those are also to be found still in service in houses built in the 1920 -30s. I have seen it. When plastic became commonly available the duration of the continuous wire insulation greatly improved and modern wire insulation could be implied to have a reasonably unexpirable duration in residential and commercial service. However, it is not so stamped because of factors beyond the reasonable control of the manufacturer.
Not at this time. Some wiring has been in continuous service for periods exceeding 80 years. Wiring does deteriorate. Insulation decomposes, connections oxidize, conductors are embrittled. However, Steps taken 100 years ago to regulate and standardize wiring practice have allowed most installations to fail safe.
