There is no technical reason to for anyone to spend that much for this particular cable to connect a TV to the ATV when another will do the same job. Computer gaming I understand can run at crazy high bit rates but not watching TV.
A correctly certified for the requirements passive cable should work if the devices hardware HDMI are compatible and software settings correct. The not working is more likely a faulty cable or a cheap knock off and a claiming it is certified when it is not. Then return it.
Buy Premium High speed that are certified and from a reliable vendor with a good returns policy. More than enough for the HDMI hardware in the ATV and your TV. All the rest is a rip off. Its your wallet.
Specs for ATV HDMI hardware are 2.0a (b??). Specs for HDMI 2.1 (meant for 8K tv) have only just been released for adoption and testing. A certain expensive cable released in advance of the testing and hope it will pass is a long shot. It may well pass, or not, but the 2.1 spec that cables will be tested for and called "Ultra High Speed" has only just started?
https://www.hdmi.org/news_events/index.aspx#CTS2018
https://www.hdmi.org/manufacturer/hdmi_2_1/index.aspx
It would not surprise me that there will be a lot cheaper set of "Ultra" certified cables available when the correct testing process is up and running. I am going to laugh my socks off if the combined cost of "Premium" and future certified "Ultra" is still less than this cable in the Apple shop. Of course I will need an 8K TV to need to buy one.
The HDMI spec is a minefield for the unwary. They really need to tighten up on it and better inform the consumer so they can make a better informed decision when they go to certain stores stocking certain products to fleece the customers.
PS. I have some prime land for sale, come see me at
low tide 6pm.
Edit. Don't take my word for it.
https://www.avsforum.com/forum/168-hdmi-q-one-connector-world/