it's tendency to always 'be there' could also be said about my right shoe.
Swing and a miss. Will your shoe still be here in 100 years, still bearing the changes you made to it while you were alive? No, probably not. I would certainly not choose a shoe to be my legacy when I can contribute code to something that will hopefully be around in some form or other well after I'm not.
hopefully.. but maybe some people who wrote games which are now long lost thought the same thing?
with the way platforms are being locked down left right and center who is to say home development will be viable 20 years from now? who is to say you'll actually be able to store ROMs on a HDD, not be forced to work in the cloud where your 'illegal files' could be pulled at will?
of course there will always be demand for developers, so development boxes will always exist, but if they end up out of the price range of regular people then what happens?
don't get me wrong, I do like to think I'm making a contribution to society and helping to preserve our culture with MAME and MESS, a mark which will last through the test of time but sometimes you have to wonder, if you look at society as a whole bigger things have been lost than either MAME or MESS.