Essentially yes... primarily because I assume hexOS is NAS software and it's claim to fame is "Sensible Defaults" that make it easy and i guess one of those assumptions is that you have more than one disk so you dont lose all your data when (not if) it dies. I'm honestly a little confused as to why you'd try to do this with HexOS? not really the intended use case
p.s.. the libertarian in me says you can do what you want but the rational adult in me says don't be stupid... -\_(--)_/-