The point is that age itself shouldn't be as much of a concern as maintenance is.
I'm not saying the T1s SHOULD last to 60 years, but if they are so profusely concerned that line 2 will have to be shut down because they can't get replacements on hand in time, common sense would've dictated a rebuild several years ago (say, 2017-18), so that the subway cars are in fine form to keep going if their replacements are delayed, but also that it wouldn't have been a total waste of money if the replacement cars had been available as scheduled. We've seen this nonsense time and again, the CLRV replacement was not on time, the SRT replacement was not on time, the GM replacement was not on time - AND there is no guarantee that the replacement cars wouldn't have been lemons that would have required the T1s to keep going even longer. It is the height of stupidity to assume that it will be and that no actions need to be taken to secure the reliable operation of line 2 going forward.
But of course, that would require a bit of planning for the future, which Toronto is terrible at. Distract the unwashed masses with promises of shiny new trains, and don't do anything about the equipment you've already got.