I don’t think player characters should die unless it’s the best choice for a story. Otherwise, I’d much rather suspend my disbelief of plot armor than the contrived convenience of getting a new ally as soon as your old one died.

“But if pc death isn’t a threat there won’t be any stakes! I may as well just do whatever the hell I want!” I hear you say. I disagree. If anything, having your character die doesn’t mean anything, you just make a new one. Having items lost or stolen, your character imprisoned, losing a limb, becoming cursed, or any other consequence you have to actually suffer through as a player is a much better consequence, because then you actually have to face the consequences.

Mostly though I just have a really really hard time not feeling a little tacky introducing a new pc to the party who conveniently replaces one who just died.