The white race is not going extinct any time soon.
>the penis argument
Believe or not, per women themselves, the most important aspect in a partner is not the penis (i would say it is the money) but even if we pretend it is, white men with big dicks exist, within this point of view, you should address the possibility that white women with access to white men with big cocks will prefer these men over blacks. And since dick size is genetic, you should address the fact the only thing that will happen within this context is filter out the males with short dick length (and while you are at it, you should also address the reason this has not happened before in history)
>the replacement argument
There is a mischaracterization within the "great replacement" narrative among race fetishists, they think that what is going on is that white nationalists and other evidentiary groups are worried about race mixing as the sole or main cause of this supposed extinction event. This is not the case, while they certainly do not approve of race mixing, the main preoccupation of these groups is the fact that while the native European and North American (white) populations are below replacement level, their governments insist on importing immigrants from the third world, this is the great replacement, not anything else. Within this framework the natural increase of imported families from the third world is more of a worry than ethnic men supposedly seducing white women.
It is also relevant to point out the fact that men with "bbc" are not the only population being imported, aside from obvious African women, Arabs, Latinos, Asians (indians and others) are among the imported ethnic groups, because of this, it would be hard to argue black men are somehow solely responsible for the changing demographic trends, and if the white race were to harshly diminish over the following centuries, it is unlikely they would be solely replaced by blacks. Latinos have a greater shot at that believe it or not, and they are not a race known to be well endowed. Another ethnic group that has a shot at it is the indians, and they are not known for their masculinity either.
>the cuck argument
Race fetishists content often presents the theme of cuckoldry, it is said the main consumers of this content are (white) men with the cuckold fetish, this is probably the case, and this has implications in regards to the psychological underpinnings of the desires of these men that go against the notion of this fetish being anything else but a simulacrum.
On the surface, one would assume the main focus of cuckoldry are the desire these men feel to be humiliated, but in regards to sexuality, there are lots of different ways of being humiliated, and cuckoldry presents but a subset of these situations, one where the control actually is in hands of the submissive men being being cheated on. Think about it, the instigator of "cuckold" like situations is always the "submissive", they are the ones requesting their partners to fuck other men, for a cuckold relationship to take place, both the "hotwife" and the "bull" must agree to perform an act before the cuck, a sexual act they could simply perform on their own if they so desired without involving the cuck, the cuck's involvement heavily implies he is the one calling the shots, otherwise, why is he present at all? The group is appealing to the cuck's tastes. Cuckolds might point to the possibility of the hotwife or the bull enjoying their presence, but, is this really the case? Some men might enjoy the though of fucking other men's partner, but do they enjoy doing so for the sake of satisfying the desires of these men?If the women involved in these activities actually buy the humiliation narratives, why would they care for the satisfaction of a man considered to be less desirable? This and many other arguments support my point here, a lot of cucks might actually agree with this, the cuckold fetish is one where an experience of humiliation is crafted within a play pretend context, now lets apply this logic to the race fetishist framework.
If it is the case there is a trend where (white) women are chasing black men to have sex with them, how come most of the content made regarding this fetish revolves around the (white) male spectator? When these women are dressed in "BLACKED" clothes, what is the appeal for black men? The same goes with the tattoos and other paraphernalia of this nature, are there any elements of this subculture that meaningfully exclude the white male element? It cannot be denied that these codes and framing are built with the supposed humiliation of the consumer of the contents within this fetish. The clothing is made for the consumers, the tattoos are an idea of the cucks (if a black male wants to be with a woman and he sees the spade tattoo in her, will he be encouraged or discouraged? He might be informed of the fact she is an slut, and STD might be a concern), the concept of "blacked" itself implies the alteration of an state that only concerns the (supposedly white) spectator, it informs him that he is being excluded from the sexual life of a woman. Why would this be of concern of a group of people that seemingly fuck because of their own desires? Blacked porn, amateur or professional, exists because of the fact there is a consumer base for it, it would not exist otherwise, as obvious as this might be, lots of race fetishists pretend to miss this fact for the sake of their kink, and i think they ought to be reminded of it.
The case is closed when we take into considerations the actual dynamics observed when blacks come to be the dominant force within a country, sadly for the cuckolds, there is little pornographic content to Haiti, unless you are into extreme misery and maybe gore, this is a tough one for them to understand, but as they are not behaving within the framework of a cuckold's fantasy, their tendencies and actions will trend towards their own benefit, engaging in performative acts for the sake of your fetish is out of the question.