You're wrong from the premise, and we have multiple cases.
Both showed cases of people upgrading and also a market expansion.
I'm sorry but your post seems to contradict itself a bit. First you tell me I'm wrong in my assumption by citing the GBA and DS revisions, but then you go on saying that: "a simple "half gen upgrade for 4K TVs" isn't as compelling a sell as a Switch gen 2, Switch gen 3, etc... Especially when Switch 2 and 3 are serving an obvious demand with more power, longer battery life, and/or different sized screen", which is the same as saying that a Switch Pro won't be enough for consumers that will, instead, hope for a new console.
About the examples provided that did work, I won't comment on the GBA => GBA SP because I didn't follow the market as much then, but the DS to DS Lite is, sorry to say, bullsh!t. First of all, the original (and ugly) DS console was in the market for only a year and 4 months before being replaced by the same spec'ed DS Lite, the DS launched in November 2004 and the DS Lite came out in March 2006, and endeing production in 2007. It was the DS Lite model the one that was available through most of the life of the DS family, obviously being able to sell more units. And on top of that, the DS Lite was cheaper from the start, $150 vs $130, and took advantage of the launch of Pokemon Diamond and Pearl as well as the explosion of casual games like Brain Training and such.
There were a lot of other factors in place to make the DS Lite sell better than just being a new model, and the launch of he DSi Lite proved that.
Please excuse my bad English.
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