Splitting shipments is different from drop shipping. Splitting shipments would be if, instead of moving a whole container of goods from a Chinese warehouse to a US warehouse, you just mail each item over by itself. Drop shipping is when you mail each item directly to the end customer.

Yes, that's why I wrote 'splitting shipments'. I don't think drop shipments to a bunch of different customers should be tariffed, that's why the de minimis exception exists in the first place.