Chromebooks. £500 for a 14" touchscreen Android/Linux/Chrome browser on x86 with a nice lit keyboard... You don't save much getting a decent-ish tablet but without Linux/keyboard etc etc. Tablets - other than £150 or so ones you can throw in a bag and take on holiday - don't really make any sense any more.
Also convertible laptops. I use a Yoga Book [1] as a laptop when traveling, which is basically just a 10" tablet (and thinner than my old iPad!). My daily driver laptop also folds all the way back (and disables the keyboard) if I want a hefty ol' 13" tablet.
As owner of an i5 Pixelbook, I was really surprised at how hot and noisy the thing became after 10 minutes playing Egg Inc. It's an interesting device (with Crostini) but not a very good tablet.
I don't use mine as a tablet (and mine is one of the ones where you can fold the keyboard right around), but it is good to have proper android support so I can use mx player to watch videos (with all codecs supported, unlike the chrome player), play lichess offline etc.
I gave up on the android tablet ecosystem this year and got a Surface Go when I needed to replace my shield tablet K1. Local suppliers sold the same Android 4 Samsung tablets I had skipped over in favour of the K1 or Amazon's limited Kindle Fire devices.
It wasn't my first choice (I'd have rathered a 7-8" device, and windows application touch support is inconsistent), but the only other option was the iPad Mini and wanted a less locked down device.
The market you refer to is dominated by Facebook, Netflix, YouTube, Spotify and maybe the Google Docs/MS Office apps. None of those require a pressure-sensitive screen and largely look and work the same way on mobile as on tablet.
Some iPad apps like Procreate and Affinity Publisher are designed for the pen, but considering that iPads sell in the tens of millions, I'd wager they make up a pretty small portion of the buying public.
From a price/performance PoV I really liked the Nvidia Shield Tablet K1, but they no longer give it updates. Even LineageOS no longer does. An update with a similar form factor but a better resolution and a little bit more horsepower would be an instant "will probably buy" (I don't really need a tablet, and am trying to not get locked into Nvidia ecosystem, so those are for me two downsides of a new Nvidia Shield Tablet K1).
To be fair to nvidia, the 2014-2018 Android 5-7 support lifecycle for the shield tablet remains the best supported android device I've owned.
I wouldn't hold out for a successor though, Nvidia makes much of the internals of the Switch and I think another Nvidia branded tablet device would be too close to competition for Nintendo to allow.
My Fairphone 2 got 4 (and will get 5) years of support from a small company (Fairphone). Tablet-wise, I agree, although the K1 refresh got less long updates. Also, I don't expect a new tablet from Nvidia for the reason you mentioned. However the setopbox line I expect updates from (don't have one but heard universal praise). Thing is, I use a Steam Link and don't have Nvidia graphics card so no GeForce Now (don't like such vendor lock in either).
Kindle Fire is dead fwiw. There were stats that Kindle line itself has slowed down but I don't know what the trajectory of iPads been like in the last two years.
