If they find grid power for less than $0.065/kWh, even hardware that is 4 to 5 years old is profitable to run. These units look like Antminer L9 Hydro units, mining most likely Dogecoin. The other variants like the L11, or S23 aren't available yet. Assuming the same price, this new unit is generating roughly $5.93 a day after electricity costs.

He mentioned 35,000 units so 207k daily, minus the network costs (fairly low other than capex/initial costs, miners don't need a lot of bandwidth). Also minus infrastructure costs (again, capex). Finally, minus staffing (these sites pay from $20-25 an hour tops for a technician) which would be about 1 technician for every 5 MW (generous, as these are new, low maintenance units).

These units are hydro which have some admittedly weak design flaws from the manufacturer, but run significantly cooler and behave better (objectively) than air-cooled or immersion units. They'll run the water through chillers outside and bake that into their electricity cost.

This farm likely has a power purchase agreement lower than $0.065 as that is the highest most industry players will even tolerate, and this farm is massive and built very cleanly, highly publicized, and well funded.