Speed Queen is still making dumb albeit electronic models. Bit pricey but solid. Or get yourself an old one off Craigslist and call someone to refurb it. Those will often outlast anything else.
A 4B is kind of the minimum for newer Librelec versions. Still cheap and fanless with a good heat sink case. I’ve learned recently about CEC and it works on my old Panasonic with Viera but I keep a little Bluetooth keyboard around too.
Speed Queen is still making dumb albeit electronic models. Bit pricey but solid. Or get yourself an old one off Craigslist and call someone to refurb it. Those will often outlast anything else.