The unmodded experience absolutely isn't a casual game. Due to the semi random nature of the game I actually rate it harder than dark souls.

It doesn't have the same roadblock encounters souls games have but you can learn how to pass them in the souls games. However in Noita you need to learn the systems and then use your knowledge of the systems to bypass the problems in a more dynamic way. For example I wanted to carve a path through lava. Usually I've done it with a freezing spell, but I didn't have it. Instead I had found lava to blood spell, so I turned parts of lava to blood which then reacted with the rest of lava to create volcanic rock, which I then dug through.

For a more casual experience I recommend using mods for whatever gives you the most trouble, because there's a lot of that can give you problems. You can learn at your own pace because it does get easier the more you get used to the systems in the game.

I definitely recommend experiencing Noita, it's one of the most unique games I've ever played. It's so unique I actually have a hard time putting it into a specific genre. I usually just call it a roguelite Metroidvania. It starts out as a roguelite but the more you play it the more it becomes like a Metroidvania where there's usually a specific mechanic preventing access to other areas but there can be multiple solutions to the mechanic and your solution depends whatever things the roguelite aspect of the game gave you.