Nvidia is doing this since forever, but now the margins are even slimmer because of the build costs. The board has the size of a minivan that needs to be cooled. NVidia is like "i gave you the boards it's on you now", and this is why the extra 800$, because you also pay the Asus, Gigabyte, branding, where as if you buy a lower tire manufacturer but the same cards, might be a bit lower, not really MSRP, but closer.
A discussion about the Nvidia GeForce RTX 5080 board has led to an interesting disclosure that might explain why some custom boards from companies like Asus and Gigabyte will allegedly launch with high price tags. However, any gamer and PC builder with some history with GeForce cards will know finding GPU stock at MSRP levels is akin to finding a pot of gold at the end of a rainbow.