Is your view useful beyond yourself? By that I mean objectively. We examine and understand the universe objectively, and try to avoid filtering the process through our bias and views.
Well, I think so / thought so. For the past 18+ years I've worked solo, so I don't really need many interpersonal skills to get by. But back when I worked in an office, my specialty was working with difficult people, helping them with computer problems, transitioning them to new computers and software. I did a lot of stuff, but that was where I really shined.
The secret of my success involved relating to each person I was working with, making them feel valued, and valuing their feelings. Considering emotions as spiritual adds value to them, reducing them to neurochemistry reduces their value. So yes, I think it's useful. Is it objective? I don't know, I think that's a little too much to expect from my own personal experiences.
The "materialists" don't make supernatural assumptions, so could that be the reason you see a problem with it?
No. Not at all. But you've said something interesting. "... don't make supernatural assumptions", but assumptions about the natural world are somehow ok? That would be a double standard, kind of hypocritical.
We have good working definitions for "material". Science works well with material, and making predictions that are reliable and verifiable. Assuming some sort of immaterial accomplishes what? I'm more interested in what you mean by "immaterial", because for we humans that is synonymous with imaginary. It's odd that you pass on what this word means in your usage since you brought it up.
Riiiiight, immaterial is imaginary. Trust, teamwork, justice, sympathy, curiosity, awe, boredom, comedy, family ... all of these are imaginary. These are arguably the most important parts of life, and for you they are imaginary. I find that hard to believe.
And, I did provide my definition of immaterial, but I didn't do it formally. As I said, this is off-topic. So no, not "odd". Getting bogged down in definitions is tedious. But, I'll restate.
Material phenomena can be measured, they behave in predictable ways, and break down over time.
Spiritual phenomena can't be measured, don't behave in predictable ways, and don't break down over time.
Meta-physical has some aspects of material, and some aspects of spiritual.
It doesn't work in every single case. Time for instance I know is material, but, saying it breaks down over time is a little wierd. I don't know enough about phenomena on a quantum scale, so those may be outliers.