Interesting mention of Hayek given that TS is big fan who has cited FH as important influence. Szasz's radical challenge to conventional psychiatry has never been leftist although it resonated with certain "liberatory" and anti-institutional aspects of 60s/70s ("Hey man, I'm doin' my own thing!). Counterculture and new left were too often conflated into "The Movement."
So-called "anti-psychiatry movement" exemplified, in many ways, political hodge-podge of the period. Big three guys - TS, R.D. Laing, David Cooper were lumped together because, "collectively", they viewed conventional psychiatry as oppressive (each cited influence of Foucault's _Madness & Civilization_ at some time or another so I guess they have that in common as well). But Szasz was always a libertarian, Laing was into psychedelics & altering consciousness, Cooper identified himself as marxist (who held that family, which lays at heart of system of repression because it enforces conformity upon and demands obedience from children, must be abolished). Michael Hoover