Let's be real, nothing has been confirmed. If it's the old Tegra there's no way it's hitting anywhere close to XB/PS levels
You're right. But we have multiple sources corroborating the fact that demos with DLSS enabled were shown during gamescom. At this point, it's as close as official as it can get without an offical statement that the thing is running a Tegra chip offering real good perfs.
I'm not sure what the old Tegra is. The actual rumored SoC is the Tegra 239, which is not old, and which should be able to run the Matrix demo just fine. Not PS5 level of fidelty, but close enough for sure.
Yes, there is still a slight possibility this one got canned and replaced with smth else, but that's unlikely given we have no leak at all regarding this supposed better SoC.
Switch 1 came out in 2017 on TSMC 20nm, which was a slightly older node nobody else really wanted to use and was hardly that great even for its time. But it was probably cheap, had the manufacturing capacity available, and was 'good enough'.
I dont think Samsung 8nm is out of the question for the same reasons. Especially if we start walking back any ideas that it's gonna be some super powerful platform, which I just dont see. That's just not what Nintendo does anymore and not only will they have a very 'affordable' price target in mind, but they also dont seem to like taking losses on hardware at any point like others will accept.
Samsung 8nm is not out of the question because we don't have the chip to check... but same here, it's mostly ruled out as T239 would be too large/hot/power hungry to get good performances out of it. And we now know that the chip offers very good performances, so we can assume it's not clocked super low as we feared in the first place.
I'm still expecting "low" clocks, but not Switch 1 levels low clocks given the perfs seem to be there.
Anyway, the leaks are now mostly coming every day, we should get a clear picture soon
Nintendo used Tegra X1 because it was the most advanced graphics IP in the mobile space at the time. And it was more advanced than GCN 1.1 in the PS4 and Xbox. It was only cheap, because 20nm was the last process without FinFet.
Honestly, my take on "why did Nintendo used the X1" would be smth like: because they dropped the ball, they had no faith in this project and wanted something cheap and already available. Maybe it was the most advanced thing for a mobile device at the time, but with more confidence and more time, Nintendo would have paid for a customized chip, with a better node process, more modern CPUs, and no useless transistors on it.
That's what T239 is actually, a customized chip dedicated to a hybrid console.