With the number of players I usually have at my table and the amount of healing and/or "stop death" spells... it is extremely rare for a character to permanently be removed from the game. I'm not against it per se... but my particular DM style does not lend itself to death being a usual possibility. I just don't run enough "encounter after encounter after encounter" adventures wherein the PCs are usually that low on stuff that they don't have what it takes to get themselves back on their feet or at the very least revivified if they do lose that final death save.
Now granted... I am lucky in that my players all tend to be a skittish bunch regardless, so that I don't NEED to actually permanently remove a character for the players to get all worked up about the possibility. They treat a lot of the fights as actual life or death because they believe it
is possible. Now if they were to actually do the math about the number of campaigns and the number of total fights across those campaigns, they'd come to the conclusion that actual death is not really likely (except in a few places where the story was such that they could die but the narrative kept them involved via undeath and such.) Thankfully they haven't caught on to it yet so these fights still seem like deadly affairs.
Truth be told... the annoying part for me isn't that my players don't think death can happen and thus take reckless actions knowing it'll work out... it's the few that believe that death is SO likely that their PCs refuse to actually take any risks at all and make their fellow party members do it for them all the time instead. You have an armored tank PC on the table, so the Ranger PC says "Oh good!" and spends all their time hiding and firing at range so that they don't get hurt-- even though they also have a really good AC and almost just as much hit points. But they still think they are a fragile flower and heaven forbid anyone sneaks through the brush to engage them. It's okay that the heavily-armored PC goers to 0 HP almost every fight because they're the only ones taking most of the hits, but you make one attack one the Ranger and suddenly they're all sullen and saying "Well, I'm dead." Sometimes I have to slap some sense into them by saying things like "Hey! Your tank is down and unconscious in the middle of the field and there are still 4 enemies around him. If you don't actually get down there and draw some attacks away from him, they're gonna kill this guy. Get a set of guts and get in there for once in your life, you whiny bastard!"
This kind of thing is where a lot of my disdain for the "winning and losing the board game" comes in... some players just put too much stock in "winning" by keeping their character alive at all costs that makes them do things that narratively don't make sense. They'll let their fellow party members get the crap kicked out of them without problem, so long as
they don't get hurt. But as I tell them... if you and your best friend went out looking for a fight and your best friend started losing once you found one... are you REALLY going to run away and hide just because YOU might get hurt? If that's the case then
why the hell did you go out looking for a fight in the first place?!?" Either play the narrative, or keep your PC home. Because it's not the other player's jobs to take all the risk while you get the rewards.