Games are a crapshoot

Not the team's lead, your lead. If you're losing lane consistently or making dumb mistakes, you're part of the problem and should focus on your own play instead of worrying about your teammates. If you truly think it's your teammates who are the only ones holding you back, take the leads I'm assuming you get through lane, and use them to help your team out. Get vision since you are ahead of the enemy laner. After you push a minion wave, even if you aren't roaming down bot, dissapear from vision so side lanes have to play safe because they're worried about you roaming. Roam sometimes to get other lanes ahead. Group for objectives and play around your teams strengths. Climbing really isn't that hard. If the game was all about luck or being vastly better than your opponent, all winrates would come closer and closer to 50%. Which for most players they aren't.