The main problem with Crawl is losing when you are attached to a character.
Losing in the beginning is not a problem, as it is difficult to care about your own low level character with no good items and no good spells/powers or no good fighting capacity, getting a kobold poisonning your level 3 character to death does not annoy me at all, because at that point i don't care yet.
But once you get nice items, good decent spells or faith abilities and can fight in interesting way, losing become frustrating because you begin to like playing with this character.
I believe that's why save scumming is so used, to avoid losing your fun with a frustrating end once you get attached to a character, because the main point of Crawl is having fun and save scumming does not remove the challenge and so the fun like wizard mode does (wizard mode giving you full health when you die, while in save scumming you will need to face the same difficulty that killed you)
I wish Crawl had difficulty modes with the classic "ironman" difficulty, that is the current Crawl game system, and an "easy" mode that would allow reloading a save instead of deleting it when your character die, with the counter effect of not counting for the score of course.
This way you'll keep the game fun for every kind of players and will not remove the challenge like Wizard mode does, as even with save scumming you'll have to face often horrible odds