Wrong point.I’d only note that Brig Gus Fair is no-ones description of a “wannabe”.
Will all four Rangers Bns deploy together? No
So there is no need for a 1* HQ. End of.
And that's before we get into the utter wastes of taxpayers money that are the infantry divisional HQs. And somehow they survive without actually delivering anything of value. Possible exception is Household Div HQ which does a bit of public duties organising.