It's just the result of some inept, internet-illiterate dummie in charge that thought they could do that and expect people to abide by it. It reeks of dumbshit, karen, midlevel managers that they think they can toss legalese into the ether with any hope of compliance. Anyone in the 'biz knows it's all under twitter's TOS which would work just fine, it's a public forum anyway.
These are the things ya love getting into at work, when you can tell the owner not to do something, and they tell you you're a stupid kid, that they've been in this business for XXYY years and how dare you..... then it causes a huge headache, and their inbox is crammed with dick picks and odd erotica, and you can charge the emergency rate PLUS overtime for the fixin's.