That is part of it, but it's not the full story. In earlier multi-core CPUs each core was basically its own chip with its own resources that could operate nearl

That is part of it, but it's not the full story. In earlier multi-core CPUs each core was basically its own chip with its own resources that could operate nearly fully independently from the other cores (although not completely independently as you still need some cache coherency mechanism and usually there would be at least a shared last-level cache). In the chiplet model the chiplets are less independent and use more shared resources, e.g. the chiplets might be designed so the memory controllers are separate from the chiplets themselves and shared between multiple chiplets. There's obviously kind of a gray area and what makes something a chip or a chiplet isn't necessarily precisely defined, but the name "chiplet" implies a model with smaller cores that use more shared resources.