It's not to say ML has no value, but predicting molecular behavior, even in the simplest system is really dam hard.
Wheb you only under 10% of the factors influencing behavior, ML doesn't get you far.
I remember working with some computational scientists:"just put a methyl group on this nitrogen and we should increase binding by 100x!".
So we make the molecule, give it to the biologists and find out binding is actually 1000x worse!