That covers twitter, now what about every other social media network. The claim was that this was happening for all of them.

Oh sorry, you're right. Here's an article[1] about Facebook, from the same outlet. With some cursory searching I couldn't find anything about other social networks hiring former three letter agency employees.

[1] https://www.mintpressnews.com/meet-ex-cia-agents-deciding-fa...

The same outlet also covered Google: https://www.mintpressnews.com/national-security-search-engin...

Here's another good source about Google's revolving door with government during the Obama administration: https://www.techtransparencyproject.org/articles/googles-rev...