Premade teams are so much stronger

I've been playing against coordinated teams in the last few games that were also 200-300mmr higher than my team and it felt like I could do nothing! Against a good team it's like wtf is going on, they will be at the right spot in the right time and you wont be able to do anything if you get ganked for example. I felt completely helpless even if you are decent mechanically with your champ, they will just abuse every mistep you make, just one step too far and you are dead. Also I play against much better teams in normals than in ranked. Ranked average they are 1200mmr in normals average is 1400mmr played against 1500mmr and 1600mmr teams (I checked on op.gg!) while we were only 1300mmr, how unfair is that?