This article is not very well-reported and feels to me like it flits between subjects without making it clear how those people actually relate to each other and how much they influenced each other. Several of the most damning things it attributes to the Collinses (who I have never heard of) are paraphrased, so I am somewhat reserving judgment until I know whether that's actually what these Collinses said. 

That said:

According to his parents' calculations, as long as each of their descendants can commit to having at least eight children for just 11 generations, the Collins bloodline will eventually outnumber the current human population. 

If they succeed, Malcolm continued, "we could set the future of our species."

This is ridiculous. There are no subcultures which average eight children except ones like Quiverfull which have incredible attrition and are also very damaging to the people raised in them. To my knowledge no historical society has averaged eight children.  'as long as each of their descendants can commit to having at least eight children for just 11 generations' is not any more plausible than 'as long as we win the lottery at least one Friday every year'.  And I think 'planning out biological children for eleven generations' is suggestive of being pretty much incompetent at thinking about the future. But since this is paraphrased, I do want to be open to the possibility that the Collinses are pursuing something much less stupid than the author implies.

The text message claiming they intend to deliberately gain influence in the effective altruist movement does give me pause, because it's one of the only parts of the article that actually quotes them in their own words. I think effective altruism is doing stuff wildly more valuable than this, and should continue to do so, and should continue to not give the time of day to reasoning of the quality on display in this article. 

But I also think they're just hilariously wrong about the odds that an altruistic movement focused on either making the world better for people alive today or on surviving the next century will be coopted by 'well, if your children commit to having eight children...' 

I have kids, and want more of them. I think the gap between peoples' desired fertility (generally above 2 kids per women) and their achieved fertility (generally below) points to an important problem for some people to think about and work on, and I think EAs who want kids should have them. I think pro-natalism is fine, and most pro-natalists don't believe any of the stuff attributed to the Collinses in this article.  But I'm not optimistic these people would be worth working with, unless the article grossly misrepresented the quality of their thinking.