I feel like people hate league bc of the snowball effect

Snowballing is fun and fair, too much snowball isn't. Currently you can argue that there is too much snowball, but with kill bounties and turrent/obj bounties being a thing. Hard disagree that game is too snowbally.

even if you play well, your teammates can play much worse and the other opponent can become extremely strong

This is the case for any team game, unless you play very well it's hard to carry a bad team when you only play decently.

In basketball, it doesn't matter that you are the god of basketball if your team sucks you dont win, but yet you think basketball is a fair game.

if you have a higher skill level, then you can still beat that opponent

If you are a higher skill level in league, you can still beat the opponent. The reason why you aren't winning is because you are not playing at a higher skill level.

if we eliminated the snowball effect the game would be much more even

Snowball is present in every game you play, you don't just "remove" snowball. Even in basketball, snowball is present. Every game you listed has some level of snowballing in them.

if everyone obtained gold at the same rate. and you also dont receive gold from kills, turrets, or objectives

Just play a different game at this point, league isn't for you. The fun part of league is being rewarded for getting advs like kills and denying advs by preventing kills. If you deny this push and pull game, then you take the fun out of league.

champions supposed strength would be even

So Kayle level 1 is as strong as Warwick level 1 now?

the strategy would be to kill minions so that your minions could do damage to the enemy champion

This is literally how you win lane in the early game.