I would actually believe it, since the ISOCELL HP2SX isn't that much bigger compared to the current GN3. Not to mention that Samsung should have lots of real-estate with the rumored form factor changes, making the Z Fold 6 as wide as the Pixel Fold.
Noted X leaker Tech_Reve says the Galaxy Z Fold6 could launch with the same 200 MP camera sensor found on the Galaxy S24 Ultra. This could be tricky as it will go against Samsung's goal of making its foldable thinner.