First, that blog post is from 2009, so this guy is not exactly “at it again.” He was at it 8 years ago – and he hasn’t updated that post since then, from what I can tell. (His most recent post on the blog is still about Catholicism, but it’s also a little bit old – from March 2016.)
Second, the non-Catholic author’s main point is that the only thing St. Irenaeus meant by “tradition” is the articles of faith enumerated in the Apostles’ Creed. But the quotes he supplies from the context of St. Irenaeus do not limit tradition to those articles of faith. St. Irenaeus spoke of many other Catholic doctrines than just the ones in the Apostles’ Creed, including: The Catholic Canon of Scripture, Doctrine versus Discipline, Peter in Rome, Peter’s Successors, The Authority of the Pope, Offering Penances for Self and Others, Mortal Sin, Sacred Images, Just War, Original Sin, Free Will, Musical Instruments, Baptismal Regeneration, Infant Baptism, The Real Presence, The Sacrifice of the Mass, Confession, Holy Days, Mary, Full of Grace, Mary, Mother of God, Mary, Assumed into Heaven, Ongoing Miracles, Private Revelation, Salvation for Non-Catholics, No Salvation Outside the Church, and Good Works. (See details and quotations for all these doctrines in the writings of St. Irenaeus by scrolling to St. Irenaeus here: historyandapologetics.com/2016/01/index-of-church-fathers-on-apologetics.html)
This is all evidence that the term “tradition” in St. Irenaeus’s work includes more than the things that author limits them to.