also done to allow more SKUs from the same components, allowing AMD to make up any mix of 8 to 64 core chips without manufacturing fixed quantities of each or disabling most of the die (expensive)
There's some truth to this in the sense that a single die would almost always have better performance than chiplets, but chiplets also reduce cost and they make larger core counts possible. A single die literally can't fit more than ~48 big cores with the associated cache and I/O, so 56, 64, or 96-core processors are only possible using chiplets.
That was indeed my point - you said it perfectly. I meant, that there is nothing for the customer in chiplets except cost.
Intel went the EMIB route to route through embedded silicon but people need to be reminded on HN that chiplet/fabric architecture is not something to brag about as a feature - which is what a lot of comments are doing (AMD did it first!). Intel went through this mess because they had to due to yield. It ain't a feature for the customer.