I would not call Madrid's public transportation network fragile. Not at all. For most practical cases, public transport won't take longer than if you need to park a car.
Not if one is lucky enough to live close enough to the city center.
From my experience in Lisbon, it took me 1h to do 30 km during rush hour and 2h outside rush hour.
As the trains/bus/boat connections get drastically reduced outside rush hour.
Ah, and good luck returning back home after mid-night.
Talking with Spanish friends, their view of Madrid network isn't much different from my experience.
In any case I was talking in general, because outside the major European cities, the transports are even worse, like 1 bus connection every two hours until 8pm and such.
I don't know Lisboa, but I can tell you this is not the case in Madrid. Neither it is in Barcelona, Paris, Brussels, Amsterdam, Berlin, ...
There can be very particular routes for which 30km can take very long (although I do not see how a 30km trip is relevant when we're talking about the centre of the cities), but this is not common. And 8pm is not late at all, it is quite easy to move at that time. Again, I do not know Lisboa, but your generalization does not fit with my experience at all.
Nice, I talk about the general case, and you list capitals and people living on the city center.
A 30km trip is relevant, because there is a large set of population that works on the city center, yet it can only afford to buy a house 30-100km away from it, and commutes every day.
I lived in middle size cities where after 8pm there are no more buses, only taxis.
You were talking, and I quote you, about "major European cities". You can easily reach most major European cities from 30km away in less than 1 hour using public transport, also after 8pm. Most middle size cities are also quite well covered, depending what you mean by middle size, but 30km away may easily be in the middle of nowhere. If this is the case you are describing, it does not apply to the case of Madrid we are discussing. It is not a generalization, it is a totally different problem.
I guess we have a complete different view what a "major European cities" city is all about.
For me major doesn't necessary mean country/region capital.
Example Coimbra and Porto are major European cities, and good luck getting in less than 1h if you happen to live outside of the happy path of bus/subway lines.
