Or at least some of them. Of course, 6 and 8-core processors are expected to have just one die (1x CCD). However, we do not know how AMD is binning products. In this case, the second die might have an issue and is disabled or in deep sleep mode. 

Yuri (1usmus) noticed that there are models out there that have a second CCD on board. While working on his Clock Tuner for Ryzen tool, the Ryzen 5 5600X was testing turned out to have a second die. This second CCD could also be read but not used. The second chiplet appears to be permanently in Deep Sleep Mode  Occasionally; something seemed to happen with it because the clock speed read increased to 550 MHz.

Presumably, the Ryzen 5 proc was originally a Ryzen 9 5900X, of which one of the two 6-core chiplets did not work properly and got binned to a 5600X. Given the still somewhat scarce availability of the Ryzen 5000 CPUs, it is not surprising that AMD still sells such a chip. Interesting is that the second die does not seem to be disabled or laser cut. There may be a way to unlock the remaining cores, similar to what one could do with certain Phenom II processors, for example. CTR will have support for detecting 'dormant' CCDs. It likely is released around the end of this month.

Ryzen 5600X and 5800X CPUs Can Have Two CPU dies