"It simply isn't cost effective for publishers to spend time tweaking their products to make the most of every possible bit of kit it might run on"
It might be time to update your knowledge of PC programming. Long gone are the days where gaming companies developed for specific "bits of kit".
These days, they develop for specific API functions that have been accepted as standard for the industry. For example, these days DirectX is at number 11, and game makers shoot for those capabilities. If your kit is compatible, then the game works. If not, well then yes, you'll have to upgrade if the game maker has not provided a secondary DX 9 path.
You are apparently confused by the amount of available hardware and its compatibility with existing games. On my existing hardware, I can play SimCity (the original version), just as I can Battle Field 3, and very many games in between. In fact, it is not my hardware that limits me so much as Windows itself - for some reason I can no longer install Microsoft FreeLancer correctly on my Win7/64 OS.
In other words, the opinion you state dates from about 15 years ago and no longer applies today.