I'd rather have an official way to have my Switch games look nicer on a 4K screen. Looks like I may go with an M Classic. Also with PS5/XSX out, something with beefier specs with DLSS could have had more REAL 3rd party support over cloud garbage.

I understand cross-gen, Twilight Princess was cross-gen, as was BOTW. But you said Nintendo prefers later remasters. Which wasn't really much of a thing before Switch with the WiiU remasters. That's all what I said. And as I said, we have Ghost of Tsushima as the lastest example that other companies do that as well.

There hasn't been any new Tegra announced or leaked which could have pointed at it, so there simply wasn't any new hardware possible apart from a Switch (ha!) to X2. But since the die-shrink of the X1, the performance advantage of the X2 would be slim at best. It's successors Xavier, Orin and Atlan, all of them being developed with the automotive industry in mind, are way too large and power-consuming to be of any use in a handheld without modification. In Xavier's case, it's the Volta GPU that was 100% geared for HPC and other industrial work and is just very unefficient as a gaming GPU. Also, Orin and Atlan are late, with Orin only really releasing next year and Atlan in 2025.

As a result, there is a distinct lack of viable option for a hardware upgrade until next year earliest unless NVidia would go on and make a totally custom Tegra chip for Nintendo, something NVidia has denied to be willing to do several times over.

Is this technically feasible? From what I recall the dock port is not fast enough to act as an extension of internal hardware, only as an upscale. Still something that can be marketed but not something that could improve fps or actual resolution/graphics. Maybe someone more informed could elaborate.

But for sure I think external add ons are the future of mid gen upgrades 

I think I get it. Makes more sense now. But I don't think Switch 2 is close though, I think it's still very far away

I think I am going to buy one of these day one just to spite some of the absolutely terrible takes I have seen about this model on the internet.

Didn't Nintendo remaster/remake all the NES Mario games for SNES?

Like I said in another thread, Nintendo may wish to keep it's SoC back on an older process node in order to not suffer the same fate as other chip manufacturers with the global shortage.
16nm FF is a good node. Old. But reliable and not congested.
Nintendo/nVidia does have room to move these designs to 12nm FF if they see the need which can accept designs from 16nm FF fairly easily... But keeping them back on 16nm is definitely the smart choice in 2021. (Even if it shits me off.)

As for Maxwell vs Pascal, throughput of those SoC's tend to be identical on a per-clock basis.
However in Pascals defense, nVidia did allot of re-working in order to mitigate any clocking bottlenecks so it was able to run at 50% higher clockrates than Maxwell. (The new node definitely helped keep power levels static however.)

Plus you also have improvements to Delta Colour Compression, one of the largest bottlenecks of the Switch and Tegra X1 is actually memory bandwidth, especially when allot of Alpha Effects come into play, DCC4 would provide Tegra X2 roughly 20% extra bandwidth through efficiency gains alone.

And then you mentioned Xavier, Orin and Atlan.
Yes they are designed for the Automotive industry, but there is a 10w Xavier variant which would offer substantial gains over Tegra X1. At 10w.

Orin and Atlan can also have cut-down designs as well, that would be suitable to the Switch. Might cost Nintendo an extra dollary-do, but it's still more than possible.

Just because a chip is designed for a certain market, doesn't meant it can't be taken and used in another market, chip manufacturers do it all the time.

USB is far to high latency and lacks the bandwidth necessary.

It can be done, but the dock would need to take-over and assume command of all processing rather than shuffle data back and forth... Then it might as well be a Switch TV device that doesn't need the handheld.