That you can see improvements in people with long covid by giving them SSRIs isn’t clear evidence it’s partly fake or a “social contagion”. Whatever improvements recorded are just as easily explained by the fact that being sick for months is depressing and alienating and a bunch of people think you’re faking it.

On top of that, the SSRI article you linked suggests a biochemical mechanism by which SSRIs might be acting (i.e. not by making something “fake” go away, by actually treating the cause of something real)