There is dispute about what was condemned at the 5th Ecuмenical Council. Origen held various views that were incorrect like the pre-existence of the soul: "Many heteroclite views became associated with Origen, and the 15 anathemas against him attributed to the
Second Council of Constantinople condemned a form of apocatastasis, along with the
pre-existence of the soul, animism, a heterodox Christology, and a denial of real and lasting resurrection of the body. Some authorities believe that the anathemas belong to an earlier local synod.
[33][34][35] ... Popes Vigilius, Pelagius I (556–61), Pelagius II (579–90), and Gregory the Great (590–604) were aware only that the Fifth Council specifically dealt with the Three Chapters, and they neither mentioned Origenism or Universalism and nor spoke as if they knew of its condemnation even though Gregory the Great was opposed to the belief of universalism." https://en.wikipedia.org/wiki/History_of_Christian_universalism#6th_century_%E2%80%93_Ecuмenical_condemnation_of_universalism?
But regardless, has the Church ever pronounced definitely on what number will be saved or won't be? In theory, one could hold anything between 1% of humanity will be saved, to 99% of humanity will be saved, even if apocatastasis was in fact condemned. But the above shows those canons were probably from an earlier local Synod, and speak only of certain Origenist theories, not all forms of apocatastasis, certainly not those of St. Gregory of Nyssa, for e.g. whom Ecuмenical Council 7 called "The Father of Fathers: "Gregory of Nyssa (c. 335/40–395) is often regarded as the most speculative and mystical thinker of the Greek Fathers.
[1] Centuries after his death, the Seventh Ecuмenical Council (787) rendered Nyssen as the “father of fathers,”" https://credomag.com/2020/07/gregory-of-nyssa-the-father-of-fathers/