Since I started 5e, and over the stretch of a half-dozen DMs, I've never seen a character death in any of the various campaigns I've been in.
In previous editions, we had lots and lots. And lots.
I'm not sure what changed. I guess, once you reach a high enough level, you're clear of insta-death from mass-damage and you, therefore, don't die from a sword wound but instead, die from failed death saves and you can usually get to a person before those death saves rack up.