Why do I keep getting into really unfair teams rank wise while queuing alone?

If you look at my op.gg then you can see that game after game my team always is having far lower ranks than the other team. I play exclusively solo and anyone who shows up in my duo history is because I run into them solely by chance. Here are some examples from the last few games.

http://prntscr.com/b4fdhu

http://prntscr.com/b4fdoi

http://prntscr.com/b4fdw5

The worst one: http://prntscr.com/b4fe3s

I'm never on the team that has higher ranks than the other team. It's not my mmr because I've been stuck in gold 1 for weeks now. Why do I keep going up against plats as teams of all/mostly golds consistently? I lose games like these automatically. Just unfair matchmaking.