But, what you say raises a question. Why is death the thing that makes it so?
Because without it, the adventure will always continue....

(or at least end in a stalemate?).
Look at it this way, suppose your party is level 1 PCs who are captured by a Archmage. You are imprisoned. Your chances of escape are zero...
or are they? If the players insist and the DM wants to run it, you might
eventually find a way to escape. The adventure goes on.
If the Archmage just
KILLS you all...
Why do you say that the threat of death is a strawman? Maybe for you, but for many of us, it adds a thrill, it spices up things and raise the tension by quite a margin when a combat comes down to a few die rolls. When the balance can tip either way it is fun.
Yeah, it isn't a strawman at all IMO.
I'm pretty sure that what
@Umbran was calling a strawman was the idea that those who are saying death shouldn't always be on the table were saying death should never be on the table. If someone doesn't want pointless random deaths, that doesn't mean characters won't die meaningfully and/or heroically.
If that was the case, sure.

If a DM wants only "meaningful and/or heroic" deaths that is of course fine.
I mean, every time a PC gets on a horse to travel anywhere, the DM could say "Roll a DEX (Animal Handling) check. What, you rolled a natural 1? Damn, you fell off your horse. (Rolls dice.) Wow... you won't believe this, you
broke your neck, man. That's unlucky; guess your PC is dead. Sorry, buddy."
If a DM and group
wanted a game like that, knock yourselves out. IMO,
anytime you choose to enter combat and any other dangerous situation, you risk death -- whether heroic or not.
That is not necessarily so. Failure can mean options are curtailed or eliminated. You failed to defeat the BBEG (but didn't die) and now the doomsday device has gone off, destroying the kingdom. There's possibly no coming back from that. You lost and the world is worse now because of it.
Yeah, but the game
goes on, doesn't it? Maybe the next adventure is a way to undo the damage and make the world better?
My point is, unless you are dead, you can always "play on" and keep going. I'm not talking about just failing one adventure, but the fact that a particular PC is done playing in it.
As I said before, without death, you might lose a battle, but the war rages on and if the DM doesn't allow for PC deaths, they will win eventually (or the players will give up).
I remember once a person posted how in their group PCs didn't die unless the player wanted them to die. I mentioned that to one of my players on Sunday when we were discussing hit points and other things and he laughed SO hard! It's fine if others want to play such a game, but it definitely isn't for me (nor I imagine anyone else in my groups, but you never know...).