I think there are three mistakes here, and they may or may not be serious, but are worth considering.
The first is the supposition that "holiness" is something manifest, in the sense it is obvious, or can be seen. Acutally, holiness, in people, is a matter of the heart and is quite invisible, and many Scriptures indicate that what appears to be holy, can be very deceptive.
The second is the interpretation of the unpardonable sin in the passage where Jesus says, (Mat. 12:31) "Wherefore I say unto you, all manner of sin and blasphemy shall be forgiven unto men: but the blasphemy against the Holy Ghost shall not be forgiven unto men," follows the casting a devil out of a blind dumb man who immediately was able to see and speak. This was an obvious demonstration of Divine power (the power of the Holy Spirit) which the Pharisees attributed to the devil. This was the unpardonable sin, attibuting the power of God to Satan.
Finally, even if all the example you gave as obvious demonstrations of holiness are true, it is not individuals that those who believe the Catholic Church is the church of the Anti-christ refer to, but the religious structure or organization. Oviously, that means some individuals in that organization must also be "evil" (and certainly there have been some who were in evil in the church in the past).
Whatever one's view, if they really believe their version of Christianity, (or any other religion) is correct, they must, if logically clear in their thinking, believe other religions and denominations are partly or completely heretical.
Only some religions believe this is license to kill the heretics, and no variety of Christianity beleives that. Nevertheless, those who believe strongly, will argue strongly. I think that's good, especially when they are arguing against me.