I'll have a look at the rest of the post when I have time, but I'm immediately suspicious about that 82m PSP number. On the Wikipedia page for PSP, it cites 3 different sources for that 82m number:
1. http://time.com/2816781/sony-to-stop-selling-playstation-portable-by-end-of-year/">An old Time article
2. A Metro article
3. The IGN article you linked.
Now, if you read the Time article, it doesn't say anything about 82m, so that's rubbish. If you read the Metro article, it says 80m, so also useless. That leaves the IGN article as the sole source for this.
If you read it, it kinda sounds like the writer/editor adding that in:
"Discussing an experience he had recently in Tokyo, in which he was given one of the last 30 PSPs ever manufactured as a present (there are 82 million PSPs in the wild), Layden suggested that because Vita hasn't followed PSP's "hockey stick" sales spike, many people assume it's in trouble. PSP, he said, was a "slow burn" over time that brought it to that number following its spike early on."
It's not Shawn Layden saying that it's 82m, it's IGN adding that in. They may have sales numbers that I'm not privvy to, but I'd doubt that.
Without the 82m, your whole argument kinda falls apart. That may be correct, but I wouldn't take a rather shaky IGN article as a source, personally.