I kind of see the High Priestess as that "as above, so below" mirror. If she shows up as a significator, it’s usually a nudge to check whether you’re actually walking your talk. She’s not some higher power herself, but more like someone who knows it exists — which also means she carries the weight of that knowledge.
She’s not perfect, but she’s not fake either. When reversed, it can point to someone who’s got some flawed beliefs — maybe about themselves, their spirituality, or their connection to something bigger — but they’re at least aware of those flaws. She’s not timid, and she usually knows she’ll have to face her choices eventually, even if she convinces herself she’s "justified" for now.
As for the “selfish gains” part — depends what you mean. If someone’s using their skills and experience to make a living, that’s not necessarily selfish; that’s just life. But if they’re knowingly pretending to understand something deeper (karma, spirit, etc.) when they don’t, that’s when it crosses into fraud territory.
Honestly, it’s not uncommon — a lot of people start down a spiritual path and never go beyond the basics. Sometimes the student just ends up outgrowing the teacher.