For oil dependence to go away, mankind either needs to give up the energy and things which are derived from petroleum or find suitable replacements, and that is a monumental challenge at this stage in the game
It's pretty easy to get oil in the quantities needed for the plastics industries without digging it up from the ground. Canola, peanuts, whales... longish-chain hydrocarbons aren't that difficult to come up with if you're willing to pay a highish price for them.
Take some time to think about how much stuff is actually made from petroleum these days... it's mind boggling.
For example, your electric batteries would possibly power a wheeled vehicle? What would those wheels be resting on? Conventional tires are made of petroleum!
For oil dependence to go away, mankind either needs to give up the energy and things which are derived from petroleum or find suitable replacements, and that is a monumental challenge at this stage in the game.