Also way back in the 1940s, computer pioneer Alan Turing determined that having developed a certain minimum requirements, any computer can simulate any other. It has to be able to address, store, retrieve, and execute. Also, loop. Once able to do enough things, it can simulate other kinds of computers, even ones with more complicated instructions, although it will be slow as cold molasses.
This has many implications. Your fancy playstation (or whatever) game can be played on your desktop PC. Old software can be run on modern computers, with a slight performance penalty, for historical accuracy. Hardware platforms can go obsolete, but their software can still be run forever. (Although the process will get more and more aggravating with time.)
A perpetual software installation would involve moving to newer, faster machines, with a proper simulator rewritten every time there was a major architecture change.