The lookup database is incredibly small and updated very infrequently. Certainly smaller and less frequent than tzinfo which is also included in the kernel
AFAICT leap seconds are announced about 6 months in advance (January/June). How would you process times that are to occur after a leap second that may or may not be?
You could store something as '2022-02-02 02:22:22 UTC', but try storing it as seconds since epoch, if you don't know if there will be leap seconds. Not to mention software that may be years or decades old.
You could store something as '2022-02-02 02:22:22 UTC', but try storing it as seconds since epoch, if you don't know if there will be leap seconds. Not to mention software that may be years or decades old.