So, the question is simply this: Whom would you trust (and why)?
The most recent version of the PineTab comes in both arm64 and riscv architectures and has everything you'd expect from a basic tablet - 10" touchscreen display, USB-C connectors, a microSD slot etc. From my experience with the PinePhone, it will very definitely be a 'DIY' machine, but if you're already using RPis and HomeAssistant you won't find that any trouble, and it is probably the closest you can get to a truly private machine.
Asus isn't necessarily clean, but it's not outright dirty either, unlike Huawei, Xiaomi, Samsung. I don't think anything these days is clean, Android or iOS. At the very least, you have spyware sending analytics, but at least avoid spyware using your data to train AI.
(Context: I code portable tools like building valuation, parking fines, election campaigning, condo security management)
But for personal use I got an iPad mini. The price of an iPad is not much higher than Android tabs. Ironically it's because I don't like the gated ecosystem, but because it's not something I'll use day to day, it's an opportunity to have something that can run Apple apps. Apple tends to attract better art, productivity, & notebook tools too.
I know that is going to sound counter to what you think you want but it will be plug and play and you can be sure it’s not going to have crapware loaded on it.
Probably not the best-value option for loading a safe Android ROM, but it is pretty recent and has a nice form factor for smart home stuff.
I tried a cheap Lenovo tab and was pleasantly surprised how little lenovo crap was on it. Additionally, it let's you uninstall pretty much everything, including their apps, plus they stay uninstalled even after system upgrade. It supports multi user, so you can have "kids space and parent space" if you want (which can have separate sets of apps). It may be obvious, but tables like Xiaomi fail on both of those aspects. Screen is a bit dark though, I have it at 100% most of the time.
I'm not sure how big screen you really need, but for cheap phones I tried Realme twice and was impressed. Their <$200 tier is perfectly usable speed-wise, look good, also has very little realme software and let's you uninstall anything (permanently).
I had zero problems with F-droid on any of those. F-droid basic updates in the background with no use intervention, so it makes an interesting tinkering device.
They have a nice list of compatible devices where you can search for upstream support [1] and really nice step by step instructions that explain how to flash the device.
I'd personally recommend to get a used Fairphone (e.g. 3/3 plus/4) because they have decent support and are repairable.
If it must be a tablet, I'd recommend to go for a Galaxy Tab because they are pretty well supported by LineageOS.
If you want a mobile Linux device, there's lots of better and more repairable alternatives when you look in the convertible laptop market.
It's coming with as high resolution 144hz display, it's encased in aluminum, the SoC is decent, their Android fork isn't terrible and according to Android Police it's expected to get support until 2027:
> Although not as prominent as the brand's smartphones, the OnePlus Pad, which launched in April 2023, is expected to receive three years of major Android OS updates and four years of security updates.