Here’s the sentence you need to pay attention to.
“Hence they could not be saved who, knowing that the Catholic Church was founded as necessary by God through Christ, would refuse either to enter it or to remain in it.336”
There are some on FR that all they do is talk about the “false doctrine” of the Catholic Church. They refuse to believe in the Real Presence and make fun of Catholics who believe in it. There are some that think you don’t have to walk through the door of a church to make to heaven, just sit in front of the TV and watch a televangelist. There are some on FR that think Christ was joking when he said you had to be baptised to be saved.
I don't ignore it at all. I reject that the Roman Catholic church was founded as necessary by God to be how anyone is saved because I know that it is by grace through faith in Jesus Christ that receiving the gift of eternal life comes and that the "church" is that body of Christ made up of all those who are IN Christ. I do not believe the Roman Catholic church is the true church. So, no, I do not "know" what the RCC claims is true. I do know what the word of God says is true and, sadly, the two have not always agreed.
So; what difference does it make?
We also 'refuse' to believe Jesus needs His MOM to open all His mail for Him; too.
We also 'refuse' to believe that your DEAD 'saints' can do ANYTHING to influence how Heaven reacts to a prayer request for below.
"They're not even [within] 100 miles [of Baghdad]. They are not in any place. They hold no place in Iraq. This is an illusion ... they are trying to sell to the others an illusion."
"They do not even have control over themselves! Do not believe them!"