No, this is incorrect. Every person in heaven IS a Saint. Some of those people have had formal declarations, but, the reason we celebrate All Saints and All Souls is to commemorate all of the people in heaven whose names we do not know, who do not have feast days.
A former pastor would take the youth group to the Catholic Cemetery this time of year, talk about how there are most likely many Saints buried in that place, we simply do not know their names. We would pray for all of the faithful departed.
What is error is for us to PRESUME anyone is in heaven (except for those who have been validly baptized and died without reaching the age of reason/had a disability where they were never responsible for personal sin OR those who had the blessing of receiving not only the Last Rites but also the Apostolic Pardon on their deathbeds then died without committing any other sins.)