What makes it a bit more confusing is that most of the time Anytype deviates from industry standards it feels like in these cases, but this time it actually just does what other tools would do as well (which is good).
As a side note to @Maira’s way of organizing with a type Project, we had the below discussion a while back where instead of a Project type, the Sets themselves act as Projects. I am still debating whether to move to that way of working or not, as it seems very appealing to me, I am just mostly afraid that they will change how things work (as well as it might be a bit much to migrate).