Anything that give developers a nightmare is never a good idea.
So protect developers and boycott nightmares!! 😶‍🌫️

I think there are obvious reasons to not like the Series S. One obvious example is that it has been a hassle for developers to port games to *sometimes*. Which means that some games take longer to come to Xbox or, worst case, don't come at all which affects Series X owners too. 

That said, the people that don't like the Series S often don't have a Series X...which I feel like the Series X owners are the only ones with a legitimate reason to not like the console. In addition, I think there is the very real point that people don't think about: how many games are coming to the Series consoles BECAUSE of the Series S? That number isn't known. You reference how without the Series S that MS would be even further behind this generation. I believe that's true. Which means that Series S could be the reason that some developers have a reason to port their game to the Series consoles to begin with from a profit standpoint. In which case, it could very well be a wash. Series S causes some hardship for developers, but it also creates opportunities for others. 

In addition, I think Series S development is great for Switch 2 owners. Switch 2 isn't on the level of Series S from a raw hardware perspective, but doing the work to port a game to the Series S means that the Switch 2 is a hop, skip, and a jump away instead of this dumbfounding and impossible seeming leap 

Generally speaking, the games that took longer to come to Xbox have been moneyhats by Sony. Meanwhile, hundreds of other games had no real issues. Even if they were technically demanding.

Every modern game generally works pretty well on low end PC and portable PCs. The way games are built these days just makes them easy to scale. As long as the hardware has a decent CPU and a lot of RAM to work with. GPU can clearly be worked around.

In my opinion it was a good idea if looked at in a bubble. Unfortunately, Microsoft majorly screwed up this generation with its focus on GamePass, its inability to develop a large amount of good exclusive games, its lack of focus, etc.

The basic idea of a less powerful console you can get for cheap is absolutely great. I payed €200 for my Series S two years ago and to this day, whenever I get the itch to buy a PS5 or Series X I just look at the hardware prices and am instantly turned off. I know this is subjective, of course; I prefer handhelds and hybrids (be it the Switch, PSP / Vita or things like Retro Gaming handhelds), so traditional home consoles aren't my go-to choice when it comes to gaming. But the Series S was an easy purchase for me, simply because it was so cheap.

What people on message boards and hardcore gamers in general tend to forget is that many people don't give a damn about 4k or 120fps. Many people just want to get to the content, i.e. the games. I'm a huge Resident Evil fan and I played RE7, RE8, 2 Remake and 4 Remake on Series S and not once did the weaker hardware lessen my enjoyment of these titles.

Case in point: I'm playing Hogwarts Legacy on Switch 2 right now and I'd already purchased that on Series S but didn't play that version a lot, partly because I couldn't play the game on the go. I know the game looks better on PS5 Pro, but I just don't mind. The Switch 2 version (which the internet says is just the PS4 version and that version apparently sucked balls) hardly looks any different to the Series S version to my eyes and I'm perfectly fine with it being 30fps.

TL;DR: The Series S itself was a good idea. Everything surrounding it was bad, though.

I have a Series X, has little to do with not liking the Series S. I got the X for the disc drive as its mostly 2nd hand XOne games I have used it for. 

The thing with MS is, all their new games I can play on PC for less. I haven't bought a single current gen game for Series X, so the idea of a Series S for the bedroom or something doesn't even come to mind. A 2nd hand One X that has the disc drive makes more sense!

But I do think Halo Infinite and Forza were held back by the Series S. They were not the flagship titles I was hoping for and Forza is now dead, Halo on life support. (Forza Horizon is fine although getting rather formulaic / soulless, but still excited to see what FH6 can bring)

And sure, Series S is now closest to Switch 2. The RAM bottleneck in Series S is good for Switch 2, or rather Switch 2 is good for Series S. Switch 2 has 9GB available for games and slower RAM than Series S. So the work on Switch 2 should work for Series S as well. Nintendo could of course free up more RAM of the 12GB for games, just as MS did for the Series S (although that's out of the much slower remaining 2GB) and then the puzzle of how to fit games on either becomes more complicated.

As it looks now

Series X, 13.5 GB RAM for games, 10 GB at 560 GB/s, rest at 336 GB/s
PS5, 12.5 GB RAM for games (13.7 GB on Pro) at 448 GB/s (576 GB/s on Pro)
Switch 2, 9 GB RAM for games at 102 GB/s docked, 68 GB/s handheld
Series S, 8 GB RAM for games with 'hundreds of MB' more freed up since 2022, 8GB at 224 GB/s, rest at 56 GB/s

Switch 2 will quickly outsell Series S, but Series S will continue to benefit from Switch 2 ports. 

The games are badly optimised. I uninstalled gamepass, now it sits on my desk collecting stickers, like some art piece. The occasional use as a mp4 movie player. 

They should have launched a slightly or moderately weaker and easier to manufacture Series X with two models, disk and digital. And no Series S. So basically Sony's approach.

Series X was out of stock for well over a year. It was never intended or marketed as Microsoft's main console because MS assumed the Series S would be the more popular option due to its cheap price. They were wrong. Series S didn't outsell the X because it was "more popular", it did because of higher availability. Series X, by design, was intended as a premium device catering to hardcore Xbox fans. Which is funny considering the "premium" PS5 utterly dominated both of Microsoft's offerings combined (and it could have been so much worse if PS5 wasn't production capped). MS misunderstood what gamers wanted, and they paid a hefty price for it.

Series S was a bad idea for its time, but it may not be a bad idea now. Because a lot has changed since this generation started: People's perceptions, graphics and price expectations, handhelds making a return, etc.

Bad Idea as seen from examples of quite a few devs this gen complaining about the Series S and late ports of BG3 and Black Myth: Wukong due to underpower of the system and needing extra resources for optimization.