When 4.0 hits companions have been reworked. They will be able to do every role (DPS, Heal and Tank) and during KotFE it will be possible to abandon them but you can still use them outside the story.
If this is possible, would it also be possible to do the same in the original story (lvl 1 to 50), to kill companions again like it apparently was in beta.
Back then there were some problems with crew skills or people killing a companion they needed (in terms of roles).
But with the new 4.0 system, those problems are solved.
So is this possible or is every companion already written into the KotFE story?