Nothing wrong with that. the Wii U had some good ideas. My dad uses the tablet thing to play games all the time, but pretty much none of the games where you need both the tablet controller and the TV ever get played.
This is really missing the point. It's always been about Nintendo being a generation behind in terms of tech. Going to cartridges here is born more out of necessity than innovation - blu-ray disks are by far the cheaper option, but reading those is delicate and prone to errors if the system is in motion. The PSP really had to do a lot to make their little CD-ettes stable within the system, and they were quick to abandon that once High Capacity Solid State got cheaper.
Rumor has it, it's region free so you can import your titty games.
Toilet gaming taken to the next level, being able to move around the house (go into the bedroom, living room, ect.), people who travel a lot especially long flights...The dock is also small enough to take with you an easily connect to a hotel TV, especially for super nerds who go to a bunch of cons.
To be fair, back then disks could store way more than cartridges (I think FVII would've taken like dozens of N64 Cartridges if I remember correctly). Now cartridges store as much as you could ever want, are much faster, and don't scratch.
To get games to run as nicely as Nintendo are wanting on a portable without a lot of load time, cartridges are a good fit as they are faster than disks. Probably one of the reasons the PSP used disk was because at the time is that they could store a lot more. Obviously advancements in tech have been made and sd cards/other cartridges can hold way more than before. Disks are also much cheaper, as you said.
Don't give up hope. I think it was gamestop or IGN (but I'm not sure on that) reached out to all the developers listed and most of them said the same thing almost verbadum ("we aren't confirming any titles"). So it may just be a blanket statement Nintendo had their third parties hand out.
imo based on the leaks I stated above, they have enough to slowly talk about it in little bursts until the release. I don't see why they don't so that to keep up discussion/hype. Pretty sure they did that with the new Pokemon and it worked.
Ever played a 3D game on your smart phone? Even if the three hour thing is just a devkit version with a shorter span, the tech for batteries hasn't caught up with the rest of the tech. You won't get anywhere near 6. There is literally no hardware out there that could run games that look like that on a reasonable sized device that isn't insanely expensive. Even the 3DS had a battery life of around 3-5 hrs.