Oh boy, we're doing Peter Turchin 'Cliodynamics' (which I almost typed 'Cliomancy' which seems about as accurate) discourse again. So my views on the matter were expressed here, from the last time we did Cliodynamics-Discourse:https://twitter.com/BretDevereaux/status/1327041776109154307 …
Though I think it matters a great deal that the PNAS paper on coin hoards exists within a fairly robust scholarly debate and doesn't claim to be the last word. For more on that debate, see L. De Ligt, Peasants, Citizens and Soldiers (2012)