It concerned extant liquid water flows on Mars. I checked again and the tool actually correctly summarised a conference paper [1]. The authors changed the wording in the abstract from "confirms" to "strongly supports" in the actual paper [2]. So the mistake AI made here was in selecting the (obscure) conference paper with 7 citations over the actual paper with over 400.
We now know though that the perchlorate detection may have been an instrument error and satellite imagery constraints water content of the RSL to below what would be expected from brine flows. It's not conclusive though and there is no consensus whether the RSL are caused by liquid or dry processes or some combination of both.
