Earlier quoted context omitted.
This take depends on the munificence of the local retailers deciding all on their own (because there's no external pressure apart from other retailers in the same position) to lower the price of their goods (and therefore reduce their profit) once the tariffs have forced the foreign goods off the market. I don't believe it for a second. Here's something that has happened before though. During the American War of Trea…
Tariffs/subsidies should be weaned off over time. Their success absolutely does not depend on "local retailers [why are you even talking about retailers when it is all about manufacturers?] deciding all on their own to lower their prices". The external competitors are still there and will just come back when tariffs are lowered, so domestic manufacturers are forced to become cost competitive.
The economic problem is that so long as the production cost imbalance exists, weaning off the tariffs just creates the same market forces that created the trade imbalance (and export of jobs) that created the situation in the first place.
I.e., if it inherently costs $5 to make a "widget" in Elbonia [1] and it inherently [2] costs $25 to make the identical (in every way) "widget" here [3] then while a tariff of $20/widget would make both equal in price, any reduction in the tariff will make the Elbonian made widget cheaper, and a purchaser will be incentivized to buy the Elbonian made one over the "made here" version because they, individually, save money by doing so.
So to maintain the widget making industry "here" the tariff has to be maintained. Any reduction and the cost incentives of "made in Elbonia" reappear, and the local manufacturer sees a corresponding drop in sales.
[1] Chosen only because it is not a real place.
[2] Meaning the local manufacturer cannot possibly produce one for less, due to higher costs "here" (e.g., energy costs, raw materials costs, labor costs, insurance costs, etc.)
[3] Where ever "here" is for the reader.