a LOT of people are given representative payees who probably could do without one. One does not need to be declared legally incompetent, they can just be considered unable to handle their own finances... which is basically a judgement of one person when all is said and done. It seems to depend often on diagnosis and the judge's opinion of said diagnosis and then secondarily the individual's actual personal capacity to deal with their own finances.

many who have had past psychotic experiences are given a representative payee- in practice- but they may not have much of a past of irresponsible financial behavior.

I wasn't given one, but I also didnt go into appeal and that can make a difference.