Hahaha. I like how they try and define legacy as age… not usefulness. Unix has continued to evolve over 40-years… AS/400, well, IBM calls them iSeries now? Woot.
Unfortunately working in financial services the are still out there along with Stratuses, Nonstops, Unisys, and of course IBM zOS Mainframes.
I like to remind the Stratus folks many of them run OpenVMS, so just call them DECs. HP Nonstops are just Tandems renamed. And Unisys aren’t they Burroughs? Heh. IBM Mainframes… yeah - unapologetically they are what they are. Oh well.