I just read that post, you kind of described it a little prejudicially: it doesn't *quite* say what you said it says. Like it says the Slovaks left of their own accord because they didn't like the Roma, not they were "removed" by the Roma, which makes it sound like they were kicking doors in, unless you have other sources which state that.
To be honest that sounds like the situation for every disadvantaged ethnic group on the planet, along with the "they just don't want to get educated or work" thing. This same pattern occurs worldwide wherever you have a particular minority heavily discriminated against to the point where they can't find work (including native Australians, native Americans, African Americans in some areas), and the government creates special accomodation to round them up together - it becomes a black hole of crime, disease and poverty. But that's everywhere, and every ethnicity, when dumped into that same situation.
I kind of doubt it's something intrinsic in all those native/ethnic populations rather than brought on by their environment. Note, also that it states the problems only really began after the fall of communism. Communism at least provides full employment. It's good for the most poor group, definitely, if they're going to have no work, no income under capitalism: guaranteed work under communisim, is better than starving or just handouts under a free market system. After the country went free market, this government-created Roma village ended up resembling other government-created slums in other free market countries. That can't be a coincidence.
i.e. there's nothing especially "Roma" about how that village fell apart. It's just like a housing estate in Australia or the UK. Plenty of English and Irish descent white people act worse than that here in Australia in the slum suburbs - the ones where they built giant complexes to concentrate the poor people together., and they have no "Wandering" history. Government-created slums always end up like this - that's what you get when policy dictates you cram all the poor people into one location.