Comeback potential way to high

Lately I've found it incredibly annoying that the early game just flat out doesn't matter. I've had it so many times that I crush early game, take towers, push all the way into their base, but then one bad teamfight happens and they can win (or atleast nullify our advantage) off that one fight. It's so depressing that you have to play perfectly the entire game long or else you lose instantly. The comeback potential is so ridiculously high nowadys it's not fun anymore. Every game feels like it just builds up to a teamfight around 30-40 minutes that will decide the game. The rest is just formalities.

I'm just an avarage joe in terms of skill, but I'm really demotivated when I get an amazing early game and it's all wiped away with one teamfight mid/late game. I miss the times where you could slowly build up a good, meaningful advantage. It's probably not going to change because of LCS but I hope these words of an unsatisfied player can reach some ears.