If you've already come to the point at which the updates have started to actually install, then I consider that to be the "home stretch".
I've been talking about multi-hour waits, while one core of the CPU just "churns", waiting there patiently, for the list of updates to appear.
A Vista machine (32-bit, C2D, 3GB RAM) I clean-installed recently took about three hours to get to the point you're talking about, so no, it's not a Win7-specific thing.
The "home stretch" you described takes bloody ages to run on a fresh install as well, even on Win8.0 RTM.
So is it your opinion that on anything less than a Haswell quad-core with 8GB of RAM, that Windows Update taking an insufferably long time, is acceptable? Even if the PC in question meets the "minimum system requirements"? That MS should get a pass on WU taking nearly half a day, on a fresh install, because "everybody knows" that those minimum requirements are actually a joke, and you need a far more grunty rig than that, just to do basic OS maintenance?
A fresh install scenario is not an everyday "basic OS maintenance" occurrence for the average user. Also, if you decide not to run a PC for six months and then ~60-90 patches download and install, again, that's not everyday, basic OS maintenance. Most people have their PCs on every day or at least every other day.
Those minimum requirements are not a joke, they're just not recommended system requirements.
I just did a WU check on my PC, it took 22 seconds to run. Granted, it will take longer when the monthly patch day comes, but even if it takes ten minutes in that scenario, that's hardly a big deal on a multi-core PC with enough RAM.
Also, I've just booted my Vista-era C2D 4GB laptop running Win7 64 that hasn't been booted in a while (last update installed 22/10), and it took about 1hr 40 minutes to do the initial processing of updates before installation (30 important updates, 8 optional). About 30 seconds of that time was spent at 100% CPU usage while an MSE update installed. Peak RAM usage during that time was 1.7GB. Putting this into plausible context, we're talking about an old computer that hasn't been used for just over two months (so it has missed two monthly patch cycles); it seems unlikely that the primary user of this machine would be in a serious hurry to unleash the maximum potential of this computer in such a scenario. The user could check their email, type a letter or any number of low-end tasks that probably don't benefit greatly from multiple cores. Should WU be quicker? Sure. Is it evidence of MS sabotaging older versions of Windows? No.
Obviously I meant the update process seems to hang not the whole pc if you took the short time to read my posts.
I read both your posts again; there doesn't seem to be any indication of this being what you actually mean. You didn't say "WU appears to hang", you said "I've got PCs that.... and they still hang during updates". Please don't try to blame me because you didn't word things in a way that makes what you intended to convey clear.