Should a 4 kill top lane be able to solo carry a game against a 4 kill bot lane or mid lane?

A 4 kill top lane should be able to have an impact on this game and not wait on your jungler and after that on your bot lane to win the game.

then the team with the winning top laner is far more likely to win

Top lane has little impact over the game. Repeated over and over by challenger players and even pro players(huni and soaz). The game ends too fast and bot lane scales faster than almost all top laners. Is hard to have an impact on the game in the current situation.

And yeah, I should have an impact if I heave a lead on the enemy team. Not lose the game immediately. Everyone is getting global gold from shut downs, turrets, assists. They get gold from doing nothing.

If you like the current state of the game, then play aram. That's the team game.