Back in 2011, there was a bit of toxicity, but not as much as what I'm seeing now. I've noticed that as the years have gone by, League has progressively gotten more toxic and it has increased exponentially.
Back in 2011, seeing stuff like "gg ez" was extremely rare for me. Now, it's pretty common to see in my games, from ally or enemy. It's probably happening once every 3 to 4 games, rather than once every 10-20 games back in 2011 for me.
People easily say stuff like "omfg u retard" or "kys", or stuff like that, and it's pretty common nowadays; things that mothers might slap their kids across the face for saying is being thrown around here like it's commonplace.
Given the majority gender and age demographic though, it's kind of expected that League will be toxic, and will continually become more toxic. Back in 2013, if I said that the majority of the community was toxic, it would most likely be false. Now, it's extremely hard to tell who is the majority now. I'm personally leaning towards there being more toxic members of the League community rather than good members now, given that last season, I was exposed to revolting toxic players pretty much every single day. The forum community has noticeably gotten more toxic, and the ingame community has easily gotten much more toxic since I joined in 2011.
So, yeah, for me, the community has easily gotten much more toxic, and I have been dissuading potential players from signing up for League by simply showing screenshots of some of the chatlogs I have taken (A lot of it is not pretty, and a lot of people in this forum would probably say that those don't represent the League community. I'd like to think that it represents PART of the League community, instead of brushing it under the carpet or plugging my ears and pretending that toxic members of this community don't exist). Many of my friends have also been dissuading potential new players from joining League for the same exact reason. League is a fun game, and it's fun to play with friends. Interacting with the community to me is like taking my hand to a belt sander (I've done this by accident in woodshop class, so I know the pain of having my hand hit the belt sander) at this point. While automated reports are doing their job, there are more toxic people being put into this community rather than them being kicked out; it doesn't really help that many of these toxic players flaunt that they evade bans on a consistent basis either.
The only issue I have with your post is that premade reports don't really work. Those are pretty much like junk reports and will get weeded out.