Some of them are
I've been bedside at more deaths than I can accurately recall. Most of them followed some religion or another, and there were a dozen or so that expressed peace and/or joy at the thought of the afterlife promised to them. Some of the others hoped it would be there, but expressed it with some degree of fear or doubt. The rest were honestly either not in their mind at all, or were otherwise unable to communicate towards the very end.
Christians, most of them, for what that matters. Three Muslims that I recall because you don't find many here in the rural south. All of them were awake and alert towards the end, and expresses still having faith, though they seemed to focus more on making their last days be about saying goodbye. No clue if that was them as individuals, or a facet of Islam in their lives.
The ones that were the most outright joyous were what you might call a bit obsessed with their religion, but it didn't seem to stay along denomination lines with the caveat that Catholics aren't much better represented here than Muslims, so protestants made up the majority of my religious patients, period.
Only ever had one Hindu patient that was dying, and he never mentioned it at all. He just wanted to cuddle with his wife and enjoy good food.
But shit, one the happiest people I ever sat with as they were dying was a secular humanist. Dude was all about going out with a smile. Kept himself just high enough to feel no pain, and was otherwise essentially partying until the cancer made that impossible. Then it was just enough medication to keep pain minimized while allowing him to be aware and able to talk. But he said he was happy with his life, and expected death to be a welcome cessation of the bullshit that comes with a body.
I think the most "impressive" Christian I sat with was an retired evangelical preacher. Despite his religion, the guy was very zen about it. "The Lord will reach down for me when it is time. I'm just going to enjoy what I have until then, and praise his name with my last breath." But it wasn't some kind of crazy thing, it was said very calmly, very matter-of-fact. He shrugged a little when he said it, like it was no big deal when he went.
That guy was of one of my favorite patients tbh. We'd go walking, and just chat about whatever our minds brought up. Wasn't always deep stuff, sometimes it would just be swapping stories about ourselves. Never preached at me, not once, and I had let him know I was essentially atheist, but also Buddhist despite that. You'd think a retired preacher from the kind of church he was in would be all up my ass, but he never even hinted at that kind of thinking.
I came late to when he was passing. It was late at night, and he was a morning patient for me. He was pretty much non verbal the last two days, but he would reach out to people you hold their hands, and smile.
Some people really, truly believe. They can believe so deeply that death is either a momentary inconvenience between them and their afterlife, or is a very welcome gift from god. There's no doubt in them, no fear, but also no desire to accelerate it.
Anyway, it's obvious that nobody can speak for the billions of religious people in the world totally. Even as many deaths as I saw are a drop in an ocean of death. But it's certain that religion can bring about what you're asking.