Thanks for the details! I've quickly logged in to check your configuration, and I have found everything okay, except one option, which caused the issue in this case. As the operator the “EQUALS” was selected for the filter, which is a numeric operator, and it does not work with text values. I've changed it to “EXACTLY LIKE”, and it appears to be working correctly now: https://i.imgur.com/IXqDY2s.png
It's a very common mistake, I've done it countless times before.
I believe you are doing a good job here, I would definitely recommend using WP Posts, not pages, as pages does not support taxonomy terms (categories, tags), and you might need them in the future.Best,
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