Games are a lot more exciting when there's a challenge, and being able to save and reload at any time really kills said danger.
That's definitely a valid type of challenge, and I like it sometimes, but usually only with shorter types of games. There are still different kinds of challenges available even when you can save and reload as many times as you want, though.
In a game with that kind of scope, what I enjoy the most is figuring out how all the systems work and interact with each other and what they allow you to do. When every mistake you make sends you all the way back to the beginning and it potentially takes hours to get back to the point where something new or interesting is happening, depending on how much you've played the game before, it really, really slows down that aspect of it nearly to a halt at times. When discovery/experimentation is your favorite part of it and you're forced to slog through permutations of stuff you've already seen dozens of times for another glimpse of something new, it starts to lose its charm.
The same kind of thing affects the ARPGs that are one of the modern spinoffs of the roguelike genre, at least for me (and not surprisingly, I never, ever play them in "hardcore" mode). Throw as many procedurally generated maps/levels in them as you want to try to keep it fresh, but I
will get sick of starting new characters from level 1 just to try out all the different options and see what weird skill combinations I can come up with that actually work. If it's one of those games that's designed so you can play through again on higher difficulty levels with the same character like Diablo or Titan Quest, it's a pretty safe bet that after the first couple times I've made it through the first difficulty level I will be starting all my new characters out on the second one, and after a couple of times through the second, all new ones will start by default on the third, and so on. Even if I have to use a mod or "cheat" to do so (I play single-player, so whatever, it doesn't affect anyone else).
It's totally a personal preference/taste thing, though. I don't expect to convince anyone to agree with me, because I don't actually think they're wrong. I get why people like permadeath in games like these, because there is definitely something to be said for the added risk vs. reward that you don't usually get anywhere near that degree in other games. I guess it's that exact same risk vs. reward proposition that's the same reason that other people dislike them, though, because they're attracted to or enjoy different elements of the game and don't find the reward nearly rewarding enough to put up with that amount of risk and end up just finding it frustrating instead.