You probably shouldn't compare the price of bread then vs the price of bread now. It's $3 in the store, but that's after decades of developing efficient methods to produce bread in gigantic quantities, which brings the consumer price down.
An artisan loaf of bread made fresh by a baker near to me costs closer to $9, for example. This would be closer to the way they made bread at the time, but even now we have modern efficiencies and easier access to ingredients.
And the fact he posted this on Juneteenth is just coincidence, right?