The Martyrologium mentions the Old Testament Saints, but usually they are not commemorated in the Liturgy, with the exception of the Maccabee martyrs. ()8-01)
I do not know the reason. Probably no one pushed their special veneration or later canonization.
I never had accessn to pre-1570 Calendar, it is possible that St Pius V cleaned them out from the Calendar.
In the good old times they were remembered in the homilies, e.g. Isaias in Advent time, when his book is read, Jeremias in Passion time, Abraham on Quinquagesima etc
I would appreciate if someone could point to a link for pre 1570 Calendar