Except that's not what is happening. If you state that the source is not verifiable or reliable (even if it is) then it will likely get removed. Often the admin will block the editor who readds the material without even checking the source. If that doesn't work then the next tactic is to accuse the editor of violating [[WP:UNDUE]] and create an unbalanced article. An admin will then come along and see that because the editor used a citation template via a named <ref> tag that the number of characters rapidly increases, and just assume that the material added is causing the article to become unbalanced.

Alternatively, another tactic is to remove the entire section, not just the bit that is disputed. After the editor reverts 3 times, no matter if they object in the talk page they will be blocked.

The ultimate way to keep material removed, however, is to claim that it violates BLP. Due to the paranoia around this area (which is admittedly somewhat justified) no admin will look into it further and the default position is that the material is forbidden no matter how absurd or invalid the claim.

After you've been reverted, incidentally, it appears that the end run around discussion and consensus is to switch the archival boy tag to about 7 days and add a collapse template on the discussion thread, which prevents it from being seen by default and effectively silences the one who was blocked - which means appeals and review of the discussion become largely meaningless.