I've sort of addressed this a couple of times here, most recently in post #641:
Yeah, I sort of touched on that idea in another post. I assumed that the product and packaging cost for a charger is pretty small so eliminating it would only reduce the phone price a tiny bit (and given Apple's desire to have prices end in "9" it may not have changed the price at all! ).
The reality is that Apple actually did lower prices on some iPhones in 2020 (the year they eliminated charger and earbuds) e.g., the 256GB and 512GB iPhone 12 Pro and 12 Pro Max models were each $50 cheaper. Last year, they lowered prices on 128GB and 256GB 12 and 12 mini models by $50 each. Also, in periods of high inflation, supply chain issues, etc. even prices staying the same could be considered a reduction.