I tried to exercise a little more patience. Initially it was unable to calculate System Data even after Apple Intelligence was enabled but I just left it to settle for a longer time. When I saw that System Data amount was finally able to calculate I let it like that for some more time before disabling Apple Intelligence and it looks like it is still OK even when Apple Intelligence is off. Initially when Storage menu is opened it looks like System Data is 44 GB and Applications is 53 GB - then in few minutes System Data changes to 24 GB and Applications to 73 GB and it does not change after that.
It is not just "cosmetical" problem as if system is unable to categorize some of used storage space it can mark it as purgeable - which does not look like desirable situation...
It is not just "cosmetical" problem as if system is unable to categorize some of used storage space it can mark it as purgeable - which does not look like desirable situation...