IIRC outside of the highest difficulty level, no, there is no perma-death. Warning of potential spoilers, but here’s the link to the Wiki to Companions:
Every companion is prone to going unconscious in battle or by the player’s actions. However, depending on the difficulty the player chooses to play the game on, companions can have permadeath and be completely eliminated from the game. Having a high enough Inspiration skill allows you to heal your companions with the Emergency Medicinal Inhaler.
And @Jophiel is totally correct, it does get a bit too heavy handed and tiring after a while. Especially when it’s all so counter-productive. I have many internal theories / headcanon on a lot of it, but it does make some of the ending choices seem a bit pointless when you take even half a sec to consider it.
That’s normally only the case with action RPGs and such. There are still many turn-based party-based RPGs where you control every action of every party member.
The industry is just so big now that there’s plenty of titles of both types!
Even on the Supernova difficulty level, I set my companions to be non-aggressive and follow at long distance and they never died (I just had them for the skill boosts and ability to carry loot).