It doesn't make a difference whether it's price to performance or price to performance/features. Explaining the low sales of the GameCube with the lack of a DVD player doesn't make sense because the Xbox sold only barely more units. Then you have the Wii which didn't play DVDs nor Blu-ray, so it should be clear how little movie playback matters for console sales. This old argument about DVD playback that the GC lacked is just as poor of an excuse for the failure of the console as marketing and name of the Wii U are for the failure of that console.
Excusing the terrible sales predictions for Switch makes you look like an apologist. If you take issue with being lumped in with an unfavorable group, don't stick up for such groups.
The paragraph in the middle of your post highlights the problem the most. You ignore a much bigger reason for success in order to make the point that the reasoning of price to performance/features ratio is correct. Battery life was just another advantage that the Game Boy had over its competitors; the key to success was that the Game Boy launched with Super Mario Land and Tetris and continued to get better games than the competitors had. For the GBA SP you even fail to name its better features which were a built-in battery and a backlit screen, both of which not being present in the original GBA; and again, the library of games is what really sold the system.
The motion controller of the Wii was a means to an end; Nintendo recognized that many potential customers of video game consoles were left behind because games got more and more bloated over the years and tutorials could take an hour or more. The thing that the big Wii hits have in common is not motion controls, but the removal of the bloat and the trait to be fun games from the very first minute, whether that's Wii Sports, Mario Kart or New Super Mario Bros. The same thing holds true for the DS. Take portability away from Switch and it still has Breath of the Wild as launch title; lots of people in America and Europe don't use the portability of Switch and were still willing to pay $300 for the console anyway. Conversely, you have people who don't use the TV functionality.
Do you see where this leads? The games are at the center.
When you look at the GC and Wii U, Nintendo's two worst-selling home consoles, they feature first party lineups where actual killer apps are rare. On the GC, Nintendo took experimental directions with 3D Mario, 3D Zelda and Mario Kart, so despite Nintendo getting out quite a few important games in the first couple of years, the reception was lukewarm at best. On the Wii U, the biggest problem was to get out games in time, so by the time hits like Mario Kart 8 and Super Smash Bros. for Wii U released, the overall software release schedule was already incredibly barren, so killer apps had next to no complementary software to go along with them.
The GC and Wii U are Nintendo's two worst-selling home consoles and with both Nintendo attempted to build a game library that is as close to PlayStation as possible. This intent demanded concessions which made the consoles bland and uninteresting. Switch got doomed because Nintendo's January 2017 presentation made it clear as day that Nintendo wasn't going to serve the big third party publishers with the console. The Wii got doomed because Nintendo was so wrong to allow Sony and Microsoft to pull away by so much. But PlayStation and Xbox suck, that's why Nintendo is so successful.
Xbox sold at Gamecube levels despite having a DVD player for several reasons. Xbox was a new unproven brand. The 90's are a vast graveyard of failed "new consoles". Consumers were rightfully wary. It sold horribly in Japan. The DVD playback required a $30 add on. Had Nintendo launched the Gamecube with standard disc sizes, and built in DVD playback for no increase in price it would have helped Nintendo tremendously. This is because unlike Xbox, Nintendo was a proven brand. Unlike Xbox, Nintendo was well liked in Japan. And IMO Nintendo just had better games than Xbox.
By the time the Wii came around DVD playback didn't matter at all, because everybody already had something that could play DVDs by that time. DVD players were cheap and ubiquitous in households by 2006. They were not in 2000 and 2001. When the PS2 came out DVD players were expensive, so many parents just opted buy their kids that much wanted PS2 and use it as a DVD player, killing two birds with one stone.
Quoting people when they are down is a bad idea. You will always get a negative answer. Nintendo could have revealed a PS4 Pro level Switch in early 2017 and people still would have called it a terrible value proposition. I'm not defending anyone. Just trying to explain why using predictions from January 2017 is a bad idea. It would be like a psychologist asking people how happy they are, but only doing so after funerals, and then concluding that 95% of all people suffer from depression.
I agree that library is the most important aspect of a console. Check my first post in this thread if you don't believe me. I was never trying to argue that price to performance/features was more important than games. I was just pointing out the obvious fact that Switch has a much better price to performance/features ratio than Wii U. And from there I went on to show that most of Nintendo's successes all had good price to performance/features ratios too.
And yes, while I said that all those consoles sold on their price to performance/features ratio, I didn't mean that was the sole driving factor of sales for those consoles! (Except for the OG Gameboy, at least until Poke'mon saved it!)