Shipping by sea per item mile relative to alternative transportation methods is actually extremely efficient in emissions terms. Secondly, ecommerce might be up but overall consumption is down.
For ecommerce, "shipping" is certainly referring to shipping the item to the customer, ie. USPS/UPS/FedEx/Amazon trucks driving around.
Definitely been an increase in that.
It would still be a net loss in emissions compared to reality but less than a naive "there goes all of that fungible shipping demand forever" model as huge container ships are more efficient in emissions even though bunker oil tends to be dirtier than jet fuel. Plus overall goods consumption is certainly down with COVID.