It's one thing if you do that, but it's another that everyone who DOES do that is going all ADC or AD melee assassin. Which they do, always. They intentionally, willfully, and eagerly play into the enemy's hands; they effectively counter themselves by overspecializing (A word nobody seems to understand the definition of, as all languages have atrophied in the community). Then they have the gall to come on the forums and complain about how broken every champion but their own main is.
I've seen both sides of that, and I've countered entire teams built like that, and I've had to try and rebalance our own team that wanted to do that. Because people wholly lack any skill, creativity, or imagination that they think the only way to solo carry a game is to play Zed or Master Yi, and EVERYONE has to fall in line behind them and build around them (the Yasuo main expecting everyone to have a knock-up for his ult is the most prominent example).
I've solo carried games many times in the past as the support. AS THE GODDAMN SUPPORT. An actual one, too! If people were actually as skilled as they like to scream at the top of their lungs in all chat, they could do that, but no. They don't even want to try to think for themselves for even a microsecond and actually think through what a champion's strengths and weaknesses are. They'll just blindly read meta stats on all the champions (which they can't read properly and it doesn't even apply to them) and base all their decisions on that.
---------mid
------top
-------jng
-------adc
--------sup
