The actual expectation is that after finishing PhD, you take a journeyman position, where you can practice the skills needed in an academic career and gradually gain independence while being mentored by a senior academic. Then, if you were successful, you get a permanent position. The postdoc path fails, as there is no clear path to a permanent position. The assistant professor path fails, because the funding system requires you to become a manager without sufficient experience.
European PhDs vary in duration. The most common system is 3+2+4 years for bachelor's + master's + PhD, which is not that different from the American 4+5 years for bachelor's + PhD. (Those are nominal durations, and actual studies usually take longer.)
In most European countries, a postdoc is a nice enough middle-class job. If you are interested in an academic career after finishing PhD, you have good chances of getting a postdoc position. The real bottleneck comes after the postdoc stage, as faculty positions are scarce in most European universities.