  The age distribution of the open cluster system is a key piece of information
to decipher the star formation history of the Milky Way disk. Recently, a
remarkable earlier drop of its older end was found, which caught our attention.
Precisely, we analyzed in detail the population of open clusters older than 1
Gyr located inside a circle of 2.0 kpc from the Sun contained in the Milky Way
Star Cluster catalog, using the Data Release 3.0 of the Gaia survey, and found
that it contains a slightly larger old open cluster population with respect to
that witnessing the earlier drop age distribution. However, there are still
some aspects that deserve further attention in order to undoubtedly handle a
statistically complete cluster sample, that allows us to comprehensively know
the older end of the open cluster age distribution function. We discuss some
reasons that affect such a completeness, among them, the photometric depth of
the database employed, the performance of machine learning techniques used to
recognize open clusters, the cleaning of cluster color-magnitude diagrams from
field star contamination, etc.
