I think many European cities have seen changes in the past twenty years. Better cycling lanes, easy bicycle rental, increased public transit density and availability (eg late at night).
Yes, I forgot about petrol prices, which have increased substantially.
I'm not so sure about infrastructure improvements, at least here in Germany. I have been cycling for more than 20 years, and the infrastructure has not changed that much. Some places have improved a bit (especially in the last 5 years), but some are worse too. I feel that the experience is largely the same here. It may be different in places like Paris or London, though.
I lived and cycled in London the last 3 years, and there is a steady drumbeat of cycling improvements at all levels. Whether it's the congestion charge, cycle hire scheme, bike lanes, or even physically reconfiguring junctions with an explicitly stated goal of improving bicycle safety, there are major changes happening there.
I'm not sure how much change is happing on the continent, but based on some stories I've seen, there are many cities pushing the envelope, I think even within Germany (probably depends on the city?).
Even with the improvements you mention, London is still not exactly the most bicycle-friendly city in Europe, which is a little surprising since it's flat as a pancake. You should try cycling in Amsterdam or Copenhagen for a comparison.
