Here are the options I have found, targeted at roughly 85" (because that is what I am looking for):

Sceptre U860CV-UMRD: 4k HDR @ 60 Hz(8 ms), 300 nits LCD(DLED), 3xHDMI 2.0 (HDCP 2.2) ACR, OS: None?

Samsung QB85C-N: 4k HDR @ 75 Hz(10 ms), 350 nits LCD(VA), 3xHDMI 2.0 (HDCP ?) 1xACR, OS: Tizen 7.0, AV1 support

LG 86UR340C9UD: 4k HDR @ 120 Hz (5 ms), 330 nits LCD(DLED), 2xHDMI ? (HDCP 2.0) 1xACR, OS: webOS 6.0

ViewSonic CDE86G3: 4k (not HDR) @ 60 Hz(?? ms), 500 nits LCD(VA), 3xHDMI 2.0 (HCDP 2.2) 1xACR, OS: None?

And, because this is HN, even though it is only 65":

Flanders Scientific: XMP651: 4k HDR @ 60 Hz (?? ms), up to 4000 nits QD-OLED, 1xHDMI ? (no HDCP) 4xSDI, OS: None?

I believe none of these have Wifi. None of them is perfect. Only the Flanders Scientific model has an OLED display, but it is roughly 10x the price of the others (this is a reference monitor, which is very much not targeted at consumers). It also only comes in sizes up to 65" and only has one HDMI port, which does not support HDCP at all. If you only need 55", they have a 2000 nit display (V550) that supports regular HDMI inputs (but is still quite expensive).

Of the remaining displays, the ViewSonic is the brightest, but does not have HDR support. The LG display supports the highest refresh rate and is probably the cheapest, but only has HDCP 2.0 (I think?), and runs webOS, which I view as the least trustworthy of the options. The Samsung display is the only one with built-in AV1 support (if that matters to you). They also have some older models (e.g., BE85FX-H), which may still be available somewhat cheaper, but I can find very little information on them. None of the displays appear to support HDMI 2.1 or 2.2, so 4k HDR is limited 4:2:0 chroma at 60 Hz. The ones labeled "OS: None?" clearly have an OS (the ViewSonic one advertises a 7 second boot time, for example, despite being labeled "OS-Free"), but it does not appear to be any of the major known-problematic ones.

I have no direct experience with any of these, so I cannot prove that they are not still spying on you.