STATUS: False, but with a slight caveat
Alice the Goon has one of the oddest progressions out of any comic character you can think of.
When she debuted on December 10, 1933 in Thimble Theatre (the strip that starred Popeye), we knew nothing about her (including that it WAS a "her") except that she was a big monster who worked for the Sea Hag (click on the image to enlarge).
A month later, in a great gag that involved Wimpy changing clothes in front of Alice, we learned that this big ol' monster was a FEMALE monster! Whether Thimble Theatre creator, E.C. Segar originally meant for Alice to be, well, Alice or not has never been determined, but it's likely that he just came up with the idea later on.
At the end of the "Plunder Island" storyline, Popeye is fighting Alice and is about to throw her off of a cliff when Alice's child screams, "Mama!" Popeye stops fighting her, of course, and we learn that Alice was forced to work for the Sea Hag involuntarily.
A couple of years later, Alice shows up again, saving Popeye's son from the Sea Hag, and she was a recurring cast member from that point on.
Alice the Goon was the basis for the title of Spike Milligan's popular BBC radio show, The Goon Show.
However, Alice the Goon did NOT originate the word "goon." It has been appearing in dictionaries as early as the early 1920s, meaning "a stupid, foolish, or awkward person."
That said, it is EXTREMELY likely that the secondary meaning of the term (which has since become the primary meaning of the term), that of "a hired hoodlum or thug" WAS based upon Alice the Goon, as, well, that's what she was! Also, this secondary meaning originated in the late 1930s.
So it is extremely likely that Alice the Goon did influence the now standard meaning of the word goon, but E.C. Segar did not coin the word itself, as it was around for more than a decade before Alice the Goon came into the picture.