I doubt that I will be operating a tractor in twenty years, and you probably won’t be either, so the point is irrelevant.
I guess that would depend upon your definition of relevant;
On the farm the tractors that I run the most are the IH Magnums 7100 and 7200s.
The 7220 is a "95" the 7110 and 7130 are early "90"s so they are 30 years old and and worked
every year, the other IH's H, . 400, 560, 340 656, 1066, 1086 are all older. The Puma 125 is maybe only 10 years or so old and
the NH T6050 is a year newer. Then there are the Green ones a 4020, a pair of 4430's, and the Ford 8000 which is a "68"
model. They all run and are worked frequently.
And then my yard tractors the IH 574 a"70" is 51 years old and is parked and hooked up to my pto generator ready to go
when needed and the Branson 8050 shes only 6 years old.
But you are right I doubt that I'm still driving them 20 years from now. I am hoping for 10+ more.
I can remember when most of them came to the farm and I have run all of them for many hours.