Sure, but we're not living in the future and not every line has been electrified yet. This will create new possibilities for connections between corridors which use different energy sources and improve transportation for everyone, today.
I'm not European so my understanding of the issue may be off, but I would assume the trains are run by a private company whilst the decision to actually electrify track probably includes government involvement in each country.
Different countries may approach electrification at different paces, and having a vehicle capable of using both electrified, and non-electrified rail will give the companies flexibility in providing service along both types of routes.
Seems like a non brainer?
When we reach full electrification, these trains won't be any worse off than any full electric variants. I suppose you can argue that the diesel engine becomes dead weight but like...how significant is that actually in contrast to...the rest of the entire train?
It doesn’t even have to be “European” question, but seems a lot like the same problem at any scale. Much more locally, here in Boston, the MBTA has had to make similar trade offs between the much higher and longer term investment of electrifying tracks, and multi-mode transit that you can introduce much sooner
I am an European and the vast majority of our rail tracks is electrified. It’s not “the future”. It’s now. In The Netherlands there are hardly any diesel trains transporting people.
It's not that temporary, electrifying tracks can take decades. In Germany, many smaller towns are connected with routes that are only partially electrified, such a hybrid concept would allow the trains to run electric most of the time and only use the diesel engine on the most remote part of the journey. This is much better than not having a train access at all, where you would have to drive a car instead.
We’re sort of where we were with hybrid cars a decade or two ago. The Prius popularized a revolution in technology that made a huge impact on car efficiency and was a huge success. The technology was useful as a bridge toward fully electric vehicles.
Of course, somewhere along the line Toyota squandered their technical leadership by forgetting the difference between “was” and “is”
Anyhow, the point is electrifying tracks is a huge infrastructure investment that will take many years and piles of money. Certainly it’s a good idea and worth the investment, but you can’t just snap your fingers and “make it so”. multi-mode trains make progress in the meantime …. Assuming you don’t”pull a Toyota” and lose sight of progress