Is this your first diesel?
In any event, this is what is known as "dead pedal". If you do research, this is not a mechanical issue, but rather a software programming aspect. You can get a tuner if you want to minimize it. Note the word "minimize".
I believe on the 2014-2019, there could be up to a 2.8 second delay more so when the engine is cold.
In general, driving a diesel truck is much different than driving the equivalent gasoline truck in terms of throttle response. I drive all three manufacturers of diesel trucks at work, and while they all have their quirks, one thing that remains the same is the throttle response. I can say that the Duramax is a little more snappier (depending on the M/Y), but overall, you know you are driving a diesel truck.
Another piece of advice, is please don't delete it. First off, deleting it will not solve anything except no more emissions, maybe gain a 1-2 mpg more, and no more DEF (which is cheap on these trucks). It also makes it look bad for us fellow diesel owners and a higher likely hood of not being able to sell it down the line.
FWIW, I prefer my trucks not to be jumpy. Feels like I got more precise control over the movement of the truck. Especially backing up to a trailer or maneuvering around things.