Question about the report system

So I've had a few annoying games today where I had intentional feeders or just bad players on my team while the other team just steam rolled them. I know how this sounds, and I don't really have any proof of this without having someone watch my games, but my support and I were doing well in lane but our teams would just feed or do poorly and then the game steam rolls from there, leaving my support and I wondering why. In one of my games, a Kayle player told me that it was because we had probably been reported recently and moved into a lower class que. Is this a thing? I don't seriously remember doing anything that warranted reporting but who knows, we all have our bad days, but like, is this really a thing?