The old saying...
"If it aint broke, dont fix it"
In this case...dont junk it (the older machines)
I think that some are referring to what MS said years ago with the release of Win95, that DOS based games would run even better than in DOS. (boy was that one heck of a MS-FIB) Perhaps that same pattern of thought thanks to MS, some expect XP to run DOS stuff.
Heck, get on ebay and find an older pc for these games, or shop around at pawn shops and flea markets or liquidation sales. You would be amazed at how many older pc's are still out there at almost giveaway prices.
Or be venturous....gather up a piece from here, a piece from there, and put one together! Where there is a will...there IS a way.