The tweeter is casting this as "People who dye their hair crazy colors, might be crazy" based on the association between dyeing hair and self-reports of having seen a therapist. An alternative, less catchy but just as valid conclusion based on the skimpiness of details might be, "Social misfits more likely to seek assistance." Or even more positively, "Socially non-conforming are more open to self-understanding." All depends on the song you want to play.
It is fun fodder for speculative conjectures but without robust and controlled studies, it is, simply, speculation.
The speculation, however, conforms with even more unstructured stereotypes and anecdotal assumptions, which makes the speculative conjecture seem more robust than it is.
Is crazy hair color a cue of actual crazy as some have suggested? It appears so. N=8k. OKCupid data. pic.twitter.com/yR9fiyU4lM— Emil OW Kirkegaard (@KirkegaardEmil) June 11, 2016
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