While I like the idea of traveling by train, and I even took a night train from Munich to Budapest in the past, but on that specific route I had to share my cabin with a guy who just got released from jail a day earlier so I was not pleasantly relaxed. The fact that the cabin only had 2 bunk beds and I was pretty much isolated from other passengers and I had no way to keep my money and other important things in a safe, made me worried a lot.
The big advantage of air travel is exactly this, you don't need to spend much time in the actual plane. And the passengers are by definition under full-time supervision by other passengers, so stealing or attacks are not so easy to get away with.
Having said that, I would still prefer to take the train when it's possible. Central railway stations are usually pretty much in the best locations of most European cities, where the connections are really good.
But there is one more thing that even the article mentions:
> In general, there is strong demand for reliable and frequent services between large cities
I second that: even in Germany the I.C.E is notorious for the delays and the poor passenger experience. So there is a lot to improve for the rail operators.