The reason why many European churches are abandoned is not necessarily because Europe is more secular, but because of the massive exodus from the countryside to always larger cities. I am not sure it is such a positive development.
Many rural areas in Europe, especially in Spain, France and in the Eastern parts of Europe are depopulating. It is not only churches which are abandoned, but all sorts of building: industrial buildings, houses, sometimes whole villages.
Edit: I have no idea how to post pictures here, so I just to started a quick blog to show you a few pictures. This is the first one:
That is a house in France which the nearby village received. The mayor is looking for people to use it, but that is difficult. There are huge industrial buildings, a few pieces of land, a water mill (fully functional), etc… That is one I know, because it is large and close to where I live, but there are dozens like it.
Other edit: I’ll add a picture of a local ruined church from the 12th century, to be in the subject…
