As long as the track is in good condition and functioning well there is no need to replace it. Unless the rails get damaged it's hard to wear track out. How hard? My dad laid out a yard in 1978 using Atlas switches with plastic frogs. They stayed in service under heavy traffic until they were replaced in 2020. By that time 42 years and literally hundreds of thousands of wheels passing over them had worn out the plastic frogs. Other switches that were hand built around the same time are still in service and not showing similar wear as they have all metal parts. Like I said, as long as the rails aren't damaged they will hold for many years.