Probably just better chiplets with the fused limits set a bit higher to match.
You can see why AMD would do it when you see Cinebench R20 results on sites like CPU Monkey:
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Would help them eke out another few % in reviews and force re-testing with the latest UEFIs, updates and drivers.
Still inferior to my 3950X @ stock settings. I definitely won the silicon lottery:
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Now if they clock higher than 2000MHz on FCLK... that might make a substantial difference.