I don't think so. They have only found another mechanism by which complex chemical reactions can be controlled. They only say that RNA is less complex because they do not understand how it works. And it only "appears" to be less complex than DNA.
The same kind of people say the appendix does not currently serve a purpose. I used to remember in high school they said that the appendix was "vestigial".
That is a strawman. RNA is more complex than DNA because it can perform enzymatic reactions. Although you are correct that less is understood about how it all works, because we are just now discovering miRNA’s, and the role they play in post transcriptional regulation of genes.
The fact that this RNA mechanism can act as a transcription factor IS a supporting data point for the “RNA world” hypothesis, because something like this would need to exist in order for there to be any sort of a complex ‘all RNA’ replicator.
Yes, the appendix is a safe have for good bugs:
“Diseases causing severe diarrhea are endemic in countries without modern health and sanitation practices, which often results in the entire contents of the bowels, including the biofilms, being flushed from the body,” Parker said. He added that the appendix's location and position is such that it is expected to be relatively difficult for anything to enter it as the contents of the bowels are emptied.
“Once the bowel contents have left the body, the good bacteria hidden away in the appendix can emerge and repopulate the lining of the intestine before more harmful bacteria can take up residence,” Parker continued. “In industrialized societies with modern medical care and sanitation practices, the maintenance of a reserve of beneficial bacteria may not be necessary. This is consistent with the observation that removing the appendix in modern societies has no discernable negative effects.”
http://www.sciencedaily.com/releases/2007/10/071008102334.htm
"Vestigial" does not necessarily mean having no function. An organ or feature can retain a purpose and still be sensibly called "vestigial" if that function is significantly reduced wrt ancestral and/or related organisms. This is certainly true of the human appendix. It is smaller and more degenerate wrt to related forms, and it's remaining functions are far less significant, and less essential, than providing for the full digestion of large quantities of raw vegetable matter.