Isn't the joke that the particular piece of toast always postdates the particular slice of bread it was made from? I.e., toast is the best thing since sliced br

Isn't the joke that the particular piece of toast always postdates the particular slice of bread it was made from? I.e., toast is the best thing since sliced bread because first we had sliced bread, and then we toasted it. It's a dumb dad joke