Checkmite
Skepticifimisticalationist
In one sense I am not surprised. Why would you allow people to post links to your competitors?
That's specious, though. Twitter is not the only for-profit social media platform but to date it is the only one that has suddenly found it necessary to blanket-prohibit general mentions of other social media sites in this manner. Clearly the balance of internet social media companies do not consider the situation to be a "competitor" dynamic in the traditional sense.