I think it’s not a good idea to conflate “spirituality” with “non-physical” or (not to mince words) “supersition.”
I realize you didn’t mean it this way, but I get a little tired of Christians calling atheists “spiritual cripples” as if we’re all unimaginative Morlocks tending our machines, with no appreciation of beauty or poetry, and no concern for matters of meaning or ethics.
As for whether we’d be better off without a belief in ghosties, I don’t think so. Clearly the problem is not so much superstitious religions as ideology. It’s all to easy for someone to say “this book has all the answers, and therefore anyone disagreeing with it is a block to progress who must be destroyed.” In the 13th century the book was the Bible, whereas in the 20th it was the Communist Manifesto or Mein Kampf. (It’s worth thinking of “The Crucible” in this regard. I remember the scenes where people tell the investigator hey, whoah, slow down- maybe we need to think about this before we start hanging people. His response was basically to say that if you doubt his perfect judgement, you’re not possessed of total faith and are therefore an enemy of the state and a witch. And the play was, of course, meant to talk about McCarthyism rather than the evils of reactionary Christianity per se.)
For that matter, there are plenty of UFO cults that don’t believe in the non-physical, but they still lead to lots of nuttery, including mass suicides.
In short, if the Catholic Church weren’t threatening to torture Galileo for disagreeing with Aristotle, someone else would threaten to torture him for the very same reason, using much the same illogic to justify their actions.
BTW, this shouldn’t be taken as resignation, or as a statement of “no matter which side wins, people will always screw things up.” I’m just saying that traditionally the problems associated with “religion” are, IMO, really problems of “ideology.” If throughout human history everyone were taught the value of skepticism and warned about the evils of ideology, we’d probably be a lot better off. (We would also have a lot fewer people believing in religions like Christianity, which IMO require their believers to jump through hoops that are a little too obviously sophistical. We might have a lot of people interpreting their personal experiences in terms of deism, though.)