Winrate in the last 20 games shows a trend for a player. In many cases, players get stuck in streaks, especially in low elo, where a little tilt goes a long way.
My last 20 games don't look great on the surface, so I wouldn't take advice from me right now, though looking at the actual games it becomes obvious that in the games I won, I did quite well, and I didn't perform horribly in most of the ones I lost (though that Trundle game was a shitshow).
Some people tank their MMR quite hard at one point or another. I remember, right around the start of Season 4, I trashed my MMR because I didn't know the real difference between ranked and norms. For a long while, my MMR sat somewhere in the low 600s until I improved and worked it back up over the course of several season resets. During the time I was restoring my MMR, I learned quite a bit about the game, and definitely made more than a few cogent arguments on the boards.
If the guy was already being shouted down by everyone else, there wasn't much reason to add your comment unless he was talking specifically to you in some comment chain, at which point, I would argue your comments were justified.
I'm at exactly a 50% winrate now in solo, and have tended to win most of my games in the past month or so. It's not hard to improve, but I usually have time for just one or two games every few days, so it takes time to climb, given variability in teammates and my own performance.
I'll definitely look into leaguecraft at some point though. Always looking to improve.
Anyway, I just like to stop in when I see comments about low rank players and game knowledge, because they don't usually come from open-minded individuals, and it's good to remind people that not every bronzie's a dumbass.