It is incredibly speculative and not very convincing. Finding a bunch of rocks similar to those formed by weather conditions on earth is not evidence that life once existed on Mars.
I think they need more biologists at NASA, and fewer people who are so eager to find signs of past life that they interpret almost anything as such a sign.
Actually back when the first Rover was exploring, it took an image of the face of a rock and then proceeded to grind the face off to see what was below. The face, before it was ground, showed what looked like a fossilized Sea Anemone ... The images may still be on NASA’s servers, but I haven’t looked in years.
NASA loves to play tricks on the public. For instance: Mars has a blue, not red, sky ... when the first color images came back to NASA’s painstakingly color corrected monitors, the moderator quickly adjusted the sky color to red ...