I’m not exactly sure what you mean by “my point of view”. My point of view in the post above is just the point of view of someone who is trying to investigate scientifically into the problem of confirmation bias causing people to become unresponsive to facts, with the hope that a strategy can become clear through scientific investigation into the material qualities of the human brain and contradictions/processes of the mind on that basis. I’m far from being at a stage of knowledge where I could propose such solutions.

Specifically in response to someone who makes an argument like the one you quoted? It would, according to my current speculation, be a matter for investigation. When I said “case-by-case” I was referring to the particular information that would be needed to make a decision in such cases.

For example, is that person somebody who is debating online for fun and to feel smart? Is it your grandma who usually is a thoughtful person but recently has passively absorbed some horrendous beliefs injected into her by mainstream media and begun to regurgitate them? Is it a person who is nihilistic and hopeless and has “accepted” this grim belief even though deep down they don’t want to think that way? Is it a person who genuinely wants to engage in good faith on that belief, or a person who is just looking to argue for fun/prestige? etc. With the scientific information about cognitive dissonance and confirmation bias, I would also think that it would be important to assess the degree to which their brain is in a stage of alleviating cognitive dissonance and able to absorb dissonance-inducing facts or not (most of the time, people will struggle to absorb dissonance-inducing facts and arguments and reject or ignore them, or not comprehend them).

There are many factors in when it would be an option to attempt to struggle with a person who says such a thing and have a potential successful outcome, which is why it would be case-by-case, determined by an assessment of that person’s readiness to argue in good faith and their reasons for holding that position and the level to which their cognitive dissonance is dampening their ability to evaluate factual information, along with one’s own ability to address the specific circumstances of that person’s state. Through this assessment you might find that there is no likelihood to argue with them successfully, and then the course of action would be to do something other than argue with them about facts.

The post I made above is to add scientific information to this question and to promote the idea of understanding more about the material basis of the formation of thoughts and opinions and the mechanisms behind confirmation bias and denial of facts, while also hoping that such knowledge could become useful eventually in struggling with people ideologically. I was not trying to offer a catch-all plan for how to argue with specific positions.

Edit: Also, if it’s not clear, I’m not disagreeing with OP. If anything, the information I shared strengthens OP’s point.