Okay, the Orbit Flow 40 sounds like the exact display I've wanted. No keyboard, piezo cells, 8 dots, cursor keys, thumb keys, USB, no extra notetaker features. However, because of the cells, I know it'll be insanely expensive. https://www.orbitresearch.com/product/orbit-flow-40/

Edit: I said originally that this has bluetooth as well as USB. It does not.

Orbit Flow 40

A compact 40 cell braille display designed for smooth, comfortable braille reading  The Orbit Flow 40 is a compact 40 cell braille display designed for computer and smartphone users who want a smooth and natural braille reading experience. Featuring high quality piezo braille cells, ergonomic

Orbit Research
@alexhall Does it actually have Bluetooth? I admit I just did a quick skim earlier so may have missed it, but it looked like it was only USB C.
@ricky_enger Huh, no, you're right. I'd also read the other new display pages, which do, so I got this one confused with those.
@alexhall And I suppose that wouldn't be so bad if it could route any audio that you'd normally have on your phone somewhere else if you needed audio for anything, since if you've got something plugged in via USB-C your phone audio is gone. I doubt they've done that, though, as it would be at odds with the minimalist approach they are taking here.
@ricky_enger That's a great point. My main use case would be with a Windows laptop, so I didn't consider what happens with a phone. Maybe it won't cause audio problems, though. If it doesn't tell iOS that it can do audio, then nothing should route to it. When I connect a hard drive to my phone, I still have audio.
@alexhall Oh, yes, that makes sense. I've had instances of plugging things in and losing audio, but I never really figured out why. I think in those instances there must've been an audio component in there somewhere.