Even some first party Nintendo games can't be relied on to run at a stable framerate so I'm going to have to disagree with you there. Link's Awakening has some nasty and inconsistent stutter issues, Breath of the Wild runs better than on the Wii U but it still has its moments.
Then you have games like Hyrule Warriors where it just feels actively bad.
Lots of Switch Games actually run a lot better under even a very mild overclock (Nintendo even officially lets the CPU get OC'd during loading screens for limited periods of time, to great effect).
This is beating the Switch on most aspects outside of first-party Nintendo library.
I think a lot of the performance problems on the switch occur when you set the resolution of the device to anything outside a fixed 720p.
I've definitely had issues with 1st party titles, but after going into the settings and forcing 720p, some did go away. At the end of the day I mostly play my Switch in docked mode with an mClassic, so the forced 720p doesn't typically detract from the experience.
However, many 3rd party titles on the Switch are just actively bad ports. Omensight, for example, which is an otherwise good game has the most atrocious port I've ever seen on a console. I would agree with you that the thread parent is off-the-mark in saying that Valve will do worse here -- PC settings are notoriously better than what you get from traditional consoles since you can actively choose to optimize them to your environment, instead of hoping some developer took the time to even try.
Then you have games like Hyrule Warriors where it just feels actively bad.
Lots of Switch Games actually run a lot better under even a very mild overclock (Nintendo even officially lets the CPU get OC'd during loading screens for limited periods of time, to great effect).
This is beating the Switch on most aspects outside of first-party Nintendo library.