After reading through the full story, this guy did something a little more than just "making memes".
Fair is fair...and I'll call it right down the middle. What this person did was illegal.
Some details about the "meme"
Mackey conspired with other influential Twitter users and with members of private online groups to use social media platforms, including Twitter, to disseminate fraudulent messages that encouraged supporters of presidential candidate Hillary Clinton to “vote” via text message or social media which, in reality, was legally invalid. For example, on November 1, 2016, in or around the same time that Mackey was sending tweets suggesting the importance of limiting “black turnout,” the defendant tweeted an image depicting an African American woman standing in front of an “African Americans for Hillary” sign. The ad stated: “Avoid the Line. Vote from Home,” “Text ‘Hillary’ to 59925,” and “Vote for Hillary and be a part of history.” The fine print at the bottom of the deceptive image stated: “Must be 18 or older to vote. One vote per person. Must be a legal citizen of the United States. Voting by text not available in Guam, Puerto Rico, Alaska or Hawaii. Paid for by Hillary For President 2016.” On or about and before Election Day 2016, at least 4,900 unique telephone numbers texted “Hillary” or some derivative to the 59925 text number, which had been used in multiple deceptive campaign images tweeted by Mackey and his co-conspirators.
A) he was trying to trick people out of voting
B) he obviously acquired his own SMS short code for fraudulent purposes (or published someone else's in order to encourage unwanted traffic to the SMS gateways) -- in either case, it's against the law
Hypothetical here in order to highlight the problem.
If I was an anti-gun activist, purchased a short code from Twilio or AWS, bought a list from a marketing company with 50,000 phone numbers of people in New York who are registered republicans, and blasted out a message (with an official looking image including the New York state seal) stating "Starting Nov 1st, permitless carry is allowed in New York provided you notify the officer if you get pulled over", and as a result, 4,900 people thought it was legitimate and got in trouble (and as a result, would end up losing their right to own firearms in their state)... I wouldn't be able to write that off as a "harmless goof".