X deprioritizes content that includes links outside of X.

As well as LinkedIn. "Put your link in the first comment and pin it" was the workaround...

They removed that a while ago.

Do you have data? Because I don't know how to see their algorithm ranking objectively enough to verify.

https://github.com/xai-org/x-algorithm

The algorithm is open source and does not include logic for down ranking external links.