Because if there are no "reputable people" speaking about it, it didn't happen, and if they did, it must be true... this is a logical fallacy called "appeal to authority" my friend.
I may be wrong, but I think it's spraying against mosquitoes. It's not just contrails, that's obvious. I've seen the same thing in my country in summer, sprayed very early in the morning. Never seen it in winter. Methinks mosquito poison, they do use planes for this.
When you see the long list of toxins they're spraying it's alarming. I read that it has something to do with HAARP but also ties in with the depopulation agenda. We watched them spray plumes that gradually came together, blocking out the sun and then it rained. The contrails are a stark difference: the ice crystals dissipate after a few minutes but the Chemtrail plumes remain for a long time.