You're missing price. Compare your trip to Public transit costs, and include infrastructure costs. You had to pay for your vehicle, your car insurance (which in the US there are irresponsibly low legal minimums), registration, gas, and also taxes for the infrastructure, to get yourself somewhere which takes up more room than needed (usually several times more room than a combination lf walking and public transit). Public transit only requires fare pricing, along with infrastructure, which is significantly cheaper per person due to more efficient use of space.

Compare many European metro cities to the US, and you'll notice their public transit is more convenient (in the characteristics you have pointed out) because we decided to shut ourselves in the foot as a country and forced everyone to have to get a car payment, while making public transit bad.

Of course, public transit isn't convenient for every area, such as rural towns in which personal vehicles are a better solution, but we have many cities where there should be significantly better public transit.