Here is a timeline:

The biggest tech giants announce the revolutionary flying car amidst never before seen record levels of promotion.

Mass production begins and the first adopters get it cheap due to government policies and green rights.

Legacy car makers start a counter campaign as more and more people switch to flying cars but the campaign inevitably fails.

The world sees a sudden spike of Air Traffic Controllers and the FAA establishes the first set of rules regarding fly driving.

Full Self Driving becomes a reality due to air navigation being less complicated. Car accidents plummet.

Sweden, Norway, Iceland are the first nations to succesfully transition to a 100% flying car infrastructure. The rest of the nations soon but surely follow suit.

CO2 emmission plummet by close to 30% worldwide as roads are being changed to green areas.

Flying car adoptions are being halted by governments due to the power grid being overused.

The power grid gets the upgrade and flying car makers resume production.

The price of the flying cars stabilizes. Traditional cars are slowly pushed out of the market as third world countries switch to used flying cars instead.

Years later: The problem of birds being pushed out of their natural air route is now solved. Light pollution remains a problem.