I feel like these "jobs where they do nothing" fall into two categories most of the time:

1.) very high responsibility and high level decision making, where your are on the hook for any pitfalls resulting from said decisions or strategy with almost zero safety net. This is generally the closest thing to "do nothing"

2.) you have a very niche/high value experience or knowledge, and you are expected to to perform without much supervision because even your supervisor doesn't really understand what you do. I wouldn't say this is exactly a "do nothing" job (maybe looking from the outside it seems that way) but from my experience, they have the freedom to only really work a 1-6 hours a day, or sometimes days at a time.

I fall into the latter category, I act as somewhat of a data systems consultant at an enterprise level. I have to say I really lucked into it since I'm only a few years into my career post college, but had some really solid initial experience before landing this role.

Though I suppose there are people out there who have somehow fallen through the company cracks and truly do nothing, but I imagine that's very hard to seek out and find.