Have they shown tariffs before on their prices?, I don't think the US had zero tariffs before Trump increased them

Previously the US's effective average tariffs were in the 1.8% range, and a big contributor there was things like vehicles and agricultural products (ie things that people were unlikely to buy on Amazon). Most developed countries are in the 1-2% range; except for the post-Trump II US, effective tariffs in double digits are basically just for extremely poor countries and weird microstates. They just weren't a significant enough part of the cost base that they'd be particularly worth highlighting.