I’d like to add another use case for multiple types.
Take a Grape object. It can be a Consumable to keep track of how much you have left, it can be an Ingredient in a recipe, it can be a Task because you need to buy some, and, if you happen to be a wine aficionado, can contain some information about the grape plant.
If Anytype is to act as a second brain, there needs to be only one Grape concept in the graph, not multiple. It might make things messy, but collapsable headers should help quite a bit.