In terms of the SDK perhaps
M1chl
is right and there's less room for improvement, because the mature toolset from PS4 has been ported over.
That said, there's a lot of code in the SDK and OS software stack that has a lot of room for improvement because it's couldn't have been ported over from PS4, i.e. the compilers and hardware driver software layers.
These will be very early software for both MS and Sony. AMD would have provided these initially, and MS and Sony would be working over time to further optimise them and iron out bugs.
PS5 hardware is new hardware. It would be a mistake to think the first batch of compiler and driver software for it would be perfectly optimized and bug free. In the world of software development this never happens.