Turns out Meta is like X and LinkedIn, it doesn’t want your links in the main post.

Users have reported seeing the following message when preparing to post a link in Facebook page posts:

A notification advises on optimizing content reach by suggesting placing links in comments instead of captions and highlights the benefit of video or photo content.

Maybe that means that you should be including all of your post links in the first comment, and an image in the main post, which is what many high-performing publishers on Facebook are currently doing.