When the new season started, there was a set of ranked missions -- the only reason why I have a rank for this season. Of all my placement matches, there was only 1 game where everyone seemed to enjoy the game, on both sides of the team. There was even a friendly conversation going on in all chat. If the majority of matches were like this one, I would actually enjoy playing ranked.
Since ranked matches generally hold a more toxic group of players who tend to blame everyone else but their selves, and elitist minded people who want everything done the way they picture it in their own head, I tend to avoid it. This applies to ranked modes across multiple games, not just League. As a result, I've played ARAM for the majority of my time on this game, and I enjoy event modes when they come around -- which sadly is few and far between now.
If you take a step back and look at people's overall behavior online, it's fairly bad in general. Now, if you're looking to enjoy multiplayer games, you're best off finding a group of players that you enjoy being with, or learning to care less about what others say or do. Also, if you put less value into what rank you are and just enjoy the game, you'll likely be less stressed when your rank changes.