When writers swap Trump for Cheeto and 45, it's not just a put-down. Removing a keyword is the anti-SEO—transforming your subject into a slippery, ungraspable, swarm.
To my experience, the phrase “bird site” was generally used as a derogatory phrase on Mastodon (represented by a Mastodon character instead of a bird), by people who were fed up by Twitter and the interactions they found there. I recall instances of it as early as April 2017.
In addition to potential SEO implications, this phenomenon is also interesting for its information theoretic implications.
I particularly like the reference in the van der Nagle paper
[…] screenshotting, or making content visible without sending its website traffic – to demonstrate users’ understandings of the algorithms that seek to connect individuals to other people, platforms, content and advertisers, and their efforts to wrest back control.
This seems like an awesome way to skirt around algorithms in social sites as well as not rewarding negative sites with clicks.