Is mining equipment purchased and paid for in advance? If so, this sounds like a few years ago in oil and gas. Prices dropping but quantities supplied rising due to sunk costs in drilling contracts.
Marginal return. The ASICs could have been bought for $10 with the expectation of making $1 a year and paying out 50¢ for electricity (a 5% yield). Now it’s making 51¢ a year (a 0.1% yield). Not enough to make economic sense, but enough to keep running the rig; 0.1% is more than zero.
Broadly, I was pushing back against the author’s inchoate claim that “the continued growth in hash power demonstrates a strong, continued belief in Bitcoin by miners worldwide.”
But betting on future price, speculation, also is important.
Also there maybe could be influence from changes in energy pricing.
An article about an ASIC startup that made HN mentioned an 12-24-month lag, IIRC, between design and mass production at scale.
So we're not even past the point of seeing the effect of the peak bitcoin value.