. there’s so much hand holding through required coursework (and homework) that one can’t hardly think deeply about anything actually original.
Take an actual graduate course in pure mathematics, very little hand holding.
there’s basically no time or space for one to explore one’s own thoughts and program unless it specifically matches up with what someone else (namely an advisor) wants to do.
Not necessarily true. Find an adviser that will support YOUR interest (they exist). Sounds like you have some biases against PhD programs without actual experience of being in a good one.