[nneonneo]

For the first point, the article explicitly examines at Bitmain’s profit margins on their devices, where they find e.g. a profit margin of 56% on the Antminer S9. Although Bitmain might be headed for increased profits in the short run, from an economic standpoint it is reasonably to assume that market participants will converge towards zero economic profit - this is a standard economic assumption.

For the second point, he’s fairly careful to specify that these are estimates from a third party (Morgan Stanley) and does not explicitly specify that he expects all of them to be Bitcoin mining rigs. The estimate of power consumption he produces here, 8.92 GW, is used merely as a check on his main figure of 7.67 GW obtained through the economic analysis; he does not directly rely on the Bitmain production figure. Plus, he also notes that this 8.92 figure doesn’t take into account the ~30% of the market not owned by Bitmain.

[mrb]

«this is a standard economic assumption.»

Yes, but given this convergence hasn't happened in years, it is unreasonable for de Vries to suggest it might happen in 7 months.

For the second point, he definitely assumes 100% of the production ends up in Bitcoin mining machine. His source says "cryptocurrency" chips, but de Vries assumes "Bitcoin" chips.