>Taxing trucks, used for transporting groceries, goods, and packages to the city, will increase the cost of each of these goods. The increase in grocery prices serves as a regressive tax on all people living within the congestion pricing zone.

You're already effectively paying a premium to account for the extra time the drivers have to spend in traffic. It's not clear whether the congestion charges will be more than the labor-time saved.

Also, a general point: typical market goods are, by default, "regressively priced", because most of them don't look at your income to determine the price. This is generally a good thing, because if every good's price scaled with income, there would be no material gain to earning an extra dollar.

Any time you recognize a real scarcity and ensure it's priced explicitly rather than allocated by an ever-choked queue, it's going to be regressive in this sense. That shouldn't be a deal-breaker by itself.