It was supposed to prove nothing. I am not an expert on Mars and on a forum full of engineers, I expected someone more knowledgeable to start taking the answer

It was supposed to prove nothing. I am not an expert on Mars and on a forum full of engineers, I expected someone more knowledgeable to start taking the answer apart systematically: this is truth, this is hallucination, this may be truth or not, but it is stated too optimistically. I can see one thing. Mars is indeed further from the Sun than the Earth, but the light on the surface is probably still comparable to a slightly cloudy day on Earth, and plants grow just fine in slightly cloudy climates.