Well, two things about that. In their interviews, Huffman says this decision making is based on Elon Musk at Twitter. I think this implies that Huffman is not basing this on numbers but on ideology and an example set by Musk. It's simply "If I'm a rich tech bro and a richer tech bro does x, I can become a richer tech bro by copying them!"
Secondly, they can crunch the numbers, it doesn't mean they are right, or that they are not subject to change in unexpected ways. Digg V4 was also a calculated decision, but they greviously miscalculated.