4k support doesn't mean that it will be more powerful and the games will be rendered in 4k, maybe is just for streaming, YouTube, and maybe simple games that can be rendered in 4k in current switch, but the system do not support.
DLSS can make its debut on consoles on switch 2.

But that's my point, that PS1 was able to achieve better looking visuals to people because of that, or at least visuals that were more appealing to consumers. So in many developer's minds they still preferred to make games for PS1 and adjusting for the 64 was too annoying. 

The DLSS part comes from another rumor, an "insider" (I really have no clue on how reliable he is) from Resetera.

Do your realize that base PS4 and Xbox One don't have 4K output and yet they have access to pretty much every streaming service available on the market? Also, there are plenty of modern devices that only support 1080p output, but are compatible with streaming services regardless like the base models of Amazon Fire Stick or Google Chromecast.

I don't know... I don't think your point makes too much sense...

PS4 was released in 2013 when 4k content or HDR was nearly nonexistent so they have legacy support. Times have changed and Nintendo has to support modern resolutions and features to be relevant for streaming platforms, better late than never.

Nintendo only really sells at a loss when their consoles aren't selling well. The 3DS was sold at a loss due to underwhelming sales and the Gamecube was selling like shit. The Switch is far from that point.

Looking at it again, this might just be a new revision that will replace the older models, not a dedicated Pro model.

I don't think that DLSS is in the cards. Nor do I think that most games will display in 4K. I think that the 4K bit is for maximum resolutions and/or video streaming. If the latter I expect Nintendo to announce Netflix soon.

In all honesty, I think that a major hardware increase simply isn't going to happen. X2, Xavier, or Orin wont be the chip. Most I could see is an X1 with an OLED screen that uses the T214 Tegra model to a higher capacity, meaning we get around 1.5-2x increase in GPU clock speed docked allowing games to run at around 1440p. And, IMO, that is best case scenario. That would also mean the battery would be more in line with the first wave of Switch's and not the second wave.

Developers preferred making games for the PS1 because the N64 was notoriously hard to program for. It used microcodes, and the easier SDK's and techniques were kept from third party developers. People attribute the texture issues to the cartridge which is "partially" true, but, in reality, the texture cache was the actual issue. Textures could have looked much better if the 4kb of texture cache didn't cause textures to have to be stretched. 

Jetson TX2 NX: NVIDIA introduces a new single-board computer with a Pascal GPU

https://www.notebookcheck.net/Jetson-TX2-NX-NVIDIA-introduces-a-new-single-board-computer-with-a-Pascal-GPU.526265.0.html

"The Jetson TX2 comes with a dual-core NVIDIA Denver 2 processor, a quad-core ARM Cortex-A57 MPCore processor and a 256-core Pascal GPU that can reach 1.3 GHz. According to NVIDIA, the Jetson TX2 NX should achieve up to 1.33 TFLOPS of AI performance and is capable of encoding H.264/H.265 in up to 4K/60 FPS at 1x. Additionally, the SBC has 4 GB of LPDDR4 RAM and 16 GB of eMMC 5.1 flash storage."

Hmmm... Interesting timing...