The first CCD is binned for the SKU's spec, the other is whatever. This has been true for all chiplet Ryzens. Though the effect used to be more extreme, I had for example a 3900X where the second CCD only managed to run at 4.1 GHz under load, compared to ~4.4 GHz on the first CCD (and 4.6 GHz being printed on the box). That's pretty common with those.