A starter base on the order of up to say 100-200 spm usually doesn't have much of a ups impact at all in my experience but I guess it could be on wimpier hardware. Or if you rely too heavily on logistics robots, but I think people usually don't go mass logistics until later.
The point of the late late game is to minimize UPS (updates per second). It becomes memory bandwindth bound at some point. It demonstrates what's possible with today's technology. In comparison, Microsoft Word can not keep up with my typing in a new, blank document.