Well, there are only five companions and you could be one of them ( If you are an Origin character) So you can save three or four and only one or two are left behind in the end.
Personal tastes aside, that is the same already done in many games, the two already mentioned, the first POE where Calisca dies in the prelude, the two Grey warden recruit companions that die in DaO and daO: Awakening, Thrask the soldier that cannot escape the Endar Spire in Kotor with you, etc etc etc.
The difference is that in those games you cannot go back and play with the ones that you left behind, it seems in this game you could go back and play with a different party in the next run, if it is made the same way it´s done in Drakensang:TROT
That said, it´s merely speculation, we would not know for sure until later. Maybe even after the final release of the game, because it´s already announced that the EA would only last for Ch1 and with only 5 companions.
Personally, I kinda like if it´s made that way. Gives me something new when I replay the game with another character.
