Reason 1:
- https://github.com/ClickHouse/ClickHouse/pull/55696#issuecomment-1774130793
Basically: Setting `date_time_overflow_behavior` applies only to
conversions between Date <-> Date32 <-> DateTime <-> DateTime64 but
it does not control the behavior of functions.
Reason 2:
- It's overkill (even if well-intented overkill). ClickHouse generally
has a garbage in - garbate out philosophy, so that should be the
default behavior which corresponds to behavior "ignore". Moreover,
function 'fromDaysSinceYearZero()' mostly exists for compatibility /
parity with MySQL and MySQL takes the same stance.
