Reducing bulling isn't the primary goal with this kind of thing, more a secondary benefit.
Did you know that heroin (at the time, that was a registered trademark) was originally sold as a "non-addictive morphine substitute" to be used as cough suppressant?
People weren't at all sure how to even regulate substances in the early years of the 20th century, which is why when the US got Prohibition it was via a constitutional amendment rather than a mere law, even though they already knew about drugs laws and the Harrison Narcotics Tax Act predated Prohibition by about 5 years.
Right now, we're not sure how to even regulate social media.
They're stopping you/others from sending DM's/Tags/Meme's(what isn't important).