Keyword rejected: Does not meet contribution guidelines

Ref#201120-023924-945000

https://www.imdb.com/title/tt4477292/keywords -- movie "Cosmos" (2019), not  to be confused with the documentaries by Carl Sagan and Neil deGrasse Tyson

I attempted to add the keyword: arecibo-message

I thought I followed the keyword guidelines carefully so I don't understand why it was rejected.

As I type this, none of the already-assigned keywords to "Cosmos" have "arecibo" as part of their name so I don't believe the rejection is due to "Cosmos" having similar keywords already.

When I click on "Check these updates" during the editing process, the other system-wide keywords that have "arecibo" as part of their name are:

• arecibo-observatory
• arecibo-radio-telescope
• arecibo-puerto-rico

But these emphasize the Arecibo location and structure, whereas an important part of the movie's story line is a visual interpretation of the binary message itself. It's a real thing as described in this Wikipedia article that looks like this:

What is shown several times in the movie is a black-and-white version of the above and because it is such a prominent graphical element, I believe it is more appropriate to add "arecibo-message" as a keyword for "Cosmos".

What did I do wrong?