Things that wouldn't otherwise be a problem will become a problem. Potentially that includes bottles, tins, plastic food packaging, niche carboard boxes.
Imports from China are ~40% of all US imports. Even a 10% drop would be difficult, and at current levels it's going to be more than that.
You mean 14%?
https://tradingeconomics.com/united-states/imports-by-countr...
So I suspect 40% figure is how many items in a typical household are from China.
Edit: in case that's not clear, here's an example:
I have one item from the USA that costs $80. I have four items from China that cost $5 each.
My imports from China are 20% of my spending. My imports from China are 80% of my goods.
If I buy a bottle of wine, a chicken, a cake, and a pint of blueberries, is it correct to say that my diet is 99% fruits? There are more than a 100 of blueberries in the pint after all.