Most extant forms of welfare exist because at the time of their creation they allowed some group of politicans to buy the votes of some subset of the population. In order to reliably capture those votes, the welfare system has to represent a substantive transfer of wealth from whoever is getting screwed to whoever is selling their vote. From this angle, the problem with UBI is it doesn't really represent a clear win…
Do you have any source on that? One of the original welfare systems, in Imperial Germany, was introduced by conservative politician Otto von Bismarck to preempt the popularity of the Social Democratic party which was gaining popularity with its proposals.
Eastern bloc ( Soviets, Warsaw pact, Yugoslavia) were dictatorships that supressed any dissent, but had very decent welfare states. There were wealth transfers, of course, but they were to the state, not citizens, and welfare wasn't linked to it.