Maybe our (european) public transportations are more developed than in the US but using them as an alternative to car is not that much easier than in the US.
It's still impossible for 90% of poeple to go take the bus because car is too expensive: They would take two hours where by car, it would take 20 minutes. For many commuters and for most of the poeple living in the outskirt, it's unfeasable.
Workers would have to leave home at 4 am and be back home at 10 pm if they had to give up cars.
It's not much the slowliness of the busses, it's the time you wait for them and the time you have to walk to and from the bus stop. If you have to take a bus + a train or a bus + a bus, you easily take more than one hour and half for a ridiculous mileage.
In such situation, you can't go to the bakery buy a bread and be back for dinner.
Also "europe" doesn't tax gas "50%" to fund public transports. Gas taxes are usualy used for roads.
That means that a higher number of cars and gas consumption didn't bring more funds to the public transport system.
Abraxas'dad is right however if we consider Eastern europe, which is completely different from western europe as public transport traditions is concerned.
In Eastern europe, after the fall of the communism, a very effective an inexpensive, yet private and profitable network of microbuses (12~15 passengers "marchrouteki") took place very quickely. Poeple didn't have cars and they developed this mean of transportation unkown in the West.
This was developed before cars became popular.

Millions of poeple still use them today in eastern europe and it's cheaper than having a car.
Microbuses drive fast (sometimes quite in sportively) and drop you anywhere you want between or at busstops. (When I say "drop" it's literaly because they realy lose no time).
The West (europe like US) could solve part of their transportation problem by sponsoring this type of vehicle. But for some reason, the superbly ignore it and prefer thinking about huge infrastructural projects costing billions.
Huge projects are not bad but a fleet of one thousand microbuses would not cost even a tiny fraction of these project and would be operative immediately.
As we are talking about solution, there is no chance at all that a policitician read this.



Inside a "marshrutka" (click to enlarge): You can talk with pretty girls (under driving license age - LOL)