premiere pro at college

How old is too old? On my community college campus, we have a ton of iMacs, but, unless I'm mistaken, only the 2019 iMac is truly worthy of using creative cloud anymore. 

I'm curious to know if we should still iMacs for any reason if they no longer serve a purpose.  At least 75% of the iMacs at our community college are 2013, while a few are 2015 and 2017. Only 1 is actually a 2019. 

Should that even matter? I mean, if the computer can't even run Microsoft Word properly, isn't is technically time to replace it?