I don't think Hearn/Warren would really care about appeasing the American market Wilder can't even sell in his own country, his return fight only did 75,000 buys in the US.
AJ's return did, reportedly, 700,000 against an equally "no-name" opponent & Fury/Chisora, again reportedly did 500,000. (Both in UK/Ireland)
Uysk's an odd one because his last 3 fights have all done 1m+ buys in the UK/Ireland alone, however 2 were obviously against AJ & the other was against Chisora in 2020. I don't think for example if he fought Jermaine Franklin he'd do even half of Fury/Chisora's PPV buys nevermind touching AJ's.
As it stands Wilder's got the lowest stock & leverage of the 4 IMO.