Another required trait, I think, is being single.
Having a family, especially young children, makes you a lot more averse to pissing away your life savings trying to make a point. Being in a relationship also means decisions are shared; it's a lot harder to get two people down the rabbit hole than one.
In cases where the FMOTL was part of a family, the husband tended to dictate things. Tom Crawford, Sean David Morton, and Robert 'Crab Bait' White come to mind.
Or, the relationship suffers. Financial problems are a major source of stress in any relationship. That's usually what drives people to freedman theories, which make their financial problems worse. Unwillingness to compromise is another major reason that relationships fail; it's practically a required trait of freedmen.
Being a FMOTL is almost antithetical to being good at human relationships. They require opposite traits. So FMOTLs tend to be anti-social types. We can see this in the online groups they form. They have no real empathy for each other (witness Burnaby's comment about no one showing up to other people's court dates), nothing in common beyond ideology, and fall out over petty things.
There's no one term to describe it all, but i think there is a profile to be found here.