It's kind of a useless question to ask, don't you think?
"Forever" is a long time. No mortal can really think ahead that far.
Also, technology advances, and people get bored with their systems, demanding new and improved gameplay and graphics. With that, developers at one point just stop developing games for an old system. A system with no new games is a dead system, so you can't keep buying new games for it forever.
So maybe you should, y'know, rephrase things a little bit. o: