I don't think it's becoming trend, it's just that when some casino don't pay — other casinos are also assumed to be same, assumptions are ofc far from truth.
I think Op is not assuming that every casino does not or no longer pays, but my assumptions is that he started this thread based on the fact that there have been several posts on this board about casinos that have refused to pay their winners of late.
And as we all know, bad news travels faster than good news, infact, most of the time, good news are not even considered as news as people tend to feel "its a normal thing, why should even be a news", but bad news travels fast as people most of the time affects readers positively or negatively in terms of emotion.
As we know, people gamble everyday, and many people win alot of money around the world, all this moneys are paid, its no news, but the moment any casino refuses to settle a winning due some issue, it becomes news instantly.