Among others. Montreal's MR-63 cars started delivery in 1965 and were retired in 2018. 53 years. Montreal's MR-73s started delivery in around 1974, and are still in service 52-years later. They are planned to be replaced in 2036 - at the age of 60 years.
NYC are still retiring their R44s, with deliveries starting in 1971, and probably all gone by the end of 2026 - 55 years service. The R42s did 50 years. The R32s from 1964 were retired in 2022 - 58 years.
The 1972 London tube stock are likely to be replaced in the late 2030s or early 2040s. Well over 60-years old, might hit 70! However the 1973 stock should be gone in 2030 - only 57 years old. The final 1938 stock was withdrawn in 2021 - 80+ years. Though the final 30 or so years was by British Rail (and successors) on the Isle of Wight.
The subway in Buenos Aires is still using some some subway cars from 1954 - over 70 years old. Paris's MP 59 (very similar to Montreal's MR-63) trains were in service for over 60 years from 1963 to 2024 while their MF 67s entered service in 1968 and won't be fully retired for 2034 - over 65 years of service.
The 1972 stock is hardly an outlier. Yeah, it requires more work as it gets older. But it's 100% an option; but harder to fund maintenance than capital costs in Ontario.