It baffles me how this could be the case given the exceedingly long development time of this particular title.
Maybe all the DLC was coded pre-launch also?
Everyone is so used to these tactics (well true RFD'ers anyhow) that even though I want to buy a game such as Mortal Kombat 11, I know I'm better served to wait for the GOTY complete edition with all the DLC that will certainly show up at some point at half the price or less. If all this DLC was free in the first place, these companies would see much higher day 1 purchases and early adopters.
1) In stock
2) Low Price
3) Quality Product