Really depends where you live. In my town I also decide when I leave, and I don't risk being late because I missed the train by one minute. I'll just take the next one. More risk of being late because of car traffic.
The problem when people compare cars to public transport is that they compare the current state of public transport in their area. We need to compare what would happen if we were spending as much billions as we do on cars.
The "flat" argument made sense a while ago in my opinion. As someone who live in a very non-flat region, biking, especially "daily life" biking was not a good solution.
This argument is now dead with the rise of electric bikes.