My latest generation 4K HDR Apple TV keeps freezing up. Any ideas as to what’s causing it and how Can I turn the thing off, now that it’s frozen?

I've had the same problem (only once so far, but in my opinion that's once too often).

The Help Desk's answer strikes me as being particularly unhelpful, almost suggesting that the problem is being caused by the owner using the unit incorrectly. There is not an acknowledgement by Apple that they're aware of the problem, accept that it is theirs to fix, and are actively working to correct it.

I don't have the option to connect via Ethernet cable, but that's beside the point.

If customers buy a unit with a stated WiFi connection capability, they have reasonable expectation that the particular connection option will work flawlessly.

Apple customers accept that they are buying products at a premium price. However, they should be getting products that provide premium performance and reliability, for a premium experience. Based on what I've read regarding this particular problem (and others which I will not cover here), customers are not getting what they paid for.

Lift your game Apple!

Rich I'm glad that the suggested solution worked for you.

However, couple of points....

I don't know what documentation you received with your unit, but what I received with mine amounted to a small slip of paper with a couple of paragraphs of simple set up instructions, none of which told me that I needed (that is, must use) an Ethernet connection.

Yes, the unit has an Ethernet port, but there are no instructions stating that it MUST be used. With regard to WiFi connections, the Help section of the Apple TV includes cautionary notes relevant to such a connection (such as positioning or proximity of the Apple TV relative to the router to guard against signal interference). I've read those notes, but they do not apply to my situation. My WiFi is working and the signal strength as measured by the Apple TV shown as maximum.

Currently, my unit is not misbehaving in terms of freezing, an I'm grateful for that. (There are issues reported by other users which apply equally to me, but I'll wait and see if future firmware updates resolve those.)

But I'm a little concerned that anyone with the freezing issue is left with the impression that a wired Ethernet connection is the only solution. If it is the only solution, then anyone who does not have ready access to such a wired solution, and who continues to experience freezes, will just have to return the unit and have their money refunded. I'm pretty sure that such an outcome would not be the one Apple would prefer.