@duffmmann while the topic of past upgrades is debatable in itself (Color's comparative performance and library of exclusives puts it beyond the mere "upgrade" league, its place better off filled by Advance whose SP model was a textbook example of an upgrade, with blackjack and backlights), we've already seen Nintendo improve on the flagship Switch model. The thought of them doing it once or twice more on a similar scale doesn't sound outside the realm of possibility - it's the zany wet dreams the fandom and the tabloids keep trying to cram into the notion on little else besides their mental fixation on Sony and Microsoft's respective midgen ventures. They even expect this thing to parrot the "Pro" part in its name!
The only point where they're truly looking back at Nintendo's history is using New 3DS's glorious handful of exclusives (which PS4P and XBO-X avoided at all) to lobby their craving for all of the contemporary AAAs on the Switch, trifles like the proportional battery and wallet tolls be damned. Otherwise, it's all about the Joneses, to the point of filling up the rumour mill with every other PS/XB-flavoured wish under the sun and expecting it to happen at once.? Including 4K, a purely aesthetic feature that even the more powerful home consoles still jump through various hoops to approach, all after Nintendo's own last investment in an aesthetic feature eventually ended with "2DS" models.
Let's face it, no matter the volume of "leaks" and "datamines", Switch Pro will NEVER sound probable until/unless Nintendo actually bothers to make it (which many including myself assume to happen anyway but in a few more years and technically kicking off Gen 10 already), because everything about it so far boils down to the TWO bullet points behind all the argumentative fluff - "I want it that way" and "Sony and Microsoft do it". DSi and N3DS actually participate in this logic less than we would like to admit.
Even if Nintendo were to announce Switch Pro in a few days, it would never undo just how ridiculous, unprofessional on the journalist side (there's a goddamn limit to how many stubbornly anonymous sources you can "cite" before losing any semblance of informative value) and increasingly self-absorbed its so-called "harbingers" will have been up to that point.
And yes, GBA SP's backlight definitely counts as an upgrade - it was a significant QoL feature directly impacting the usability of the entire device. Not just at nighttime either.? The nub on New 3DS didn't change the actual output but was similarly important despite its own remaining compromises.
@ImBackBB Heroes of Might & Magic on Gen 4 Game Boy, yeah baby.?