“The Church specifically condemned the teaching of Origen over this issue and over the issue of universal salvation. Both of these are Gnostic beliefs that ultimately lead to the pagan belief in reincarnation, which the Church flatly condemns.”
Right! Along with the teachings of Evagrius of Pontus and Didymos the Blind at the Second Council of Constantinople in 553. This is a very old but once commonly held heresy. Like so many of them, they seem to pop up in various Protestant and other extra-Ecclesial groups.
And in rare instances among individuals baptized and raised in the Church. The problem is that much of the early Christian heterodoxy, as you mention, believed it (it was popular), and is also part of Talmudic Judaism.
This makes exposure to such this heresy very likely to a casual reader of classical Greek philosophy and early Christian apologetics such as Origen and others.
Which is why the Church insists on the staying the course in the life of the Church, rather than wondering off into heterodxy where anything goes.