I agree entirely. The name "Schizo Tech" is not only inaccurate, it is incredibly offensive. It presents a view of schizophrenia that is trivialized and belittling, and the term "schizo" is often used as a slur against those suffering from mental illness. We are, as it happens, talking about an illness that the World Health Organization has deemed one of the ten most debilitating diseases out there.

If you don't like Anachronistic Tech, perhaps Eclectic Tech? Or we could take a third option....

I'm about to put in Technology Kitchen Sink as a redirect.

It would need to be "mass-produced" steel as well, otherwise your argument doesn't really apply (at which point, you're dealing with an industrialized society that might very well develop rifled fire-arms as part of a range of experimentation with different types of weapons).

Moreover, steel is frequently heavy. Sure, your foot soldiers might be able to run around in steel armor, but at what price in terms of mobility and vulnerability to other types of weapons? That's the reason why knights eventually became extinct - it became too difficult and costly to protect them from increasingly advanced guns (and this was before rifling).

On top of that, "missiles" is a broad category. Even if your civilization doesn't develop guns, they could go down the "crossbow" route, and would likely eventually get back to guns if they end up using cannons/explosives.