Potential oddball suggestion, but possibly worth considering:

Get a Steam Deck, get some kind of kickstand accessory/dock for it.

I have no clue what your exact price points or screen size/dpi, or viewing distance preferences are, but I absolutely spend way more time ‘using’ my Deck to just play videos while I am lounging in my bed… than I do using it for anything else, lol.

Also, of course, a Steam Deck is a semi-portable gaming device, and also a psuedo-laptop… you can just plug in a mouse, keyboard, and/or a fairly cheap wireless streaming dongle thingy into a TV as well, you don’t really have to bother much with a fancy low latency / fast response time set up if you’re just streaming vids or movies.

7.4 inch diagonal screen, 1280x800, ~12 hr battery life if you put it in a power save mode and just watch youtube or play a local file movie, OLED, $550 USD.

Cheaper than a flagship phone, larger screen than a flagship phone (though less dpi / lower res, but the OLED is still OLED so you have that high brightness and contrast capability), probably more expensive than a… decent enough maybe? for your use case mid-low end tablet…

But also Valve is still selling the older LCD Decks for $300, which is probably roughly the same or slightly more than a maybe decent enough mid-low end tablet.

Or you could be in not the US and be looking at a different uh, price reality.

EDIT:

https://www.amazon.com/gp/aw/d/B0BRXZDWDV

I found and use this thing… its a dock, that attaches to the Deck, has a kickstand built in… a dockstand?

So you can pretty easily just have this thing attached to the Deck but not plugged in, and your Deck is still a semi-portable thing. Its never gotten in the way of me gripping and using the Deck’s controls.

There are apparently some reviews that indicate buyers got some that were broken OOTB, but mine has worked flawlessly.

It also has a microsd slot, though, hilariously, it is kind of jank, there isn’t a spring lock/release mechanism, you just stick the sd card in there, and the sd card sticks out a bit… but I’ve been running Retro Deck off of an sd card in that slot, and it works fine.

So, now, if you have this ‘docked’, ie, plug in the power to the ‘dockstand’, well now you’ve got the Deck’s micro SD slot, as well as the 'dockstand’s micro SD slot, two USB A 3 slots, and an HDMI slot.

(The USB C slot on the ‘dockstand’ is for power transfer, not data.)

You could possibly also plug in a laptop style portable USB hub into one of these USB A 3 slots… though I have yet to try this, probably at some point you’d cap out the actual data transfer rate of the USB 3 A slot if you try to run way too much shit through it…

But it could/should work with a few low data instensity things. Like uh, i would think:

‘dockstand’ <-> ‘usb hub’ <-> ‘M+K’

would be fine in most situations, and that leaves another USB 3 A on the dockstand free for say, wireless headphones with a usb dongle, or an external harddrive that goes to USB 3 A, things you may want to have on another…tier of things that are disconnected more or less frequently, in different use cases.

EDIT 2:

Forgot to mention!

The Deck Screen is also a touchscreen.

You can poke and swipe it as a tablet or phone… or, unexpectedly for me…

When I set up a 3DS emulator… I was genuinely shocked to discover that the touch screen part of the 3DS… just fucking worked, I didn’t even have to do any extra configuration, just fucking worked, I could just poke at maps and menus the way you do on a 3DS.