Sure there are situations where bikes aren't suitable.

Bikes cost time. You have to think of the time it has cost you to earn the money to buy, run, and maintain a car.

It is much easier to take a bike with you on a train than it is a car.

If you were to say, ride a bike from Washington D.C. to Portland Oregon, they money saved on gas, maintenance, insurance, and lease payments, would amount to three times the hours of work to pay, assuming a median U.S income.

This is a ridiculous example, but, frankly, saying our main mode of transit should be cars because we might want to take a long road trip once a year is absurd. It’s an outlier use case that could be addressed with other systems more effectively.