Navi 48 is 390mm^2 while GB205 is 263mm^2 and priced at $549. They both use TSMC 4nm and TSMC increased their prices recently.
GB203 is 378mm^2 and priced at $749 and $999 depending on the card. I think AMD may struggle here, although perhaps GDDR6 is a lot cheaper than GDDR7 which might help.
RDNA3 used a GCD+MCD design which helped keep the GCD small. Only 200mm^2 in the 7800XT.
But pictures of RDNA4 show a large monolithic die.
AMD Navi 48 in real flesh The GPU is estimated at 390 mm². Navi 48, Source: Tom's Hardware Tom's Hardware captured photos of the tray holding AMD's latest
videocardz.com