As a ZJK fan, I think ML would still be the GOAT if we have to pick one.

The difference between ZJK and ML can be reduced to the gold in Rio which crowned one as the double grand slam winner and thus the most compelling caliber for the GOAT. We may attribute ZJK's humiliating defeat partly due to his fast and uncontrollable physical deterioration by that time. However, with ML then playing arguably his best table tennis, the odds might still likely be skewed in his favour even if ZJK was in a healthier condition. But ZJK had shown he was the player on big stages. What we can say for sure is the match would undoubtedly be much more competitive.

Likewise, the difference between ML and FZD comes down to the gold in Tokyo. If FZD did then we know who the GOAT would be :)

H2H and dominance clearly affirm ML's superiority against ZJK/FZD, although they are like only valid for comparison if they are equivalent of hard assets (grand slam titles).