Yes, it requires more power.
You have to consider power and the time the radio needs to be on to accomplish the task.
If using mmWave you can transfer data at 2,000Mbps and using midband you achieve 500Mbps the baseband will be on for 4x the time with midband, and it will need to use less than 1/4th the power of mmWave to break even.
Midband does not require 1/4th the power of mmWave. Closer to 1/2th.
On 11/27/22 at 5:13pm I was in the St. Louis airport and ran a speed test on my iPhone 12 Pro Max. I was probably one of the first non-diagnostic users of their mmWave infrastructure and I must have been the only user at the time because I achieved a damn-near-practical-maximum of 3938Mbps down. The only reason I ran the speed test at all was that a notoriously sluggish web application I was using was performing spectacularly.
Since then I have been running speed tests at concerts, sporting events, traffic jams, airports, shopping centers, and the Rennaissance Faire. All locations where, prior to 5G, cellular coverage was useless.
On 10/13/24 at 1:14pm I was in a crowded terminal at Chicago O'Hare and ran a speed test on an iPhone 15 Pro Max. Connected via mmWave I achieved 1869Mbps down.
And Airports, and Parks, and Ampitheateaters, and Malls, and Theme Parks...
mmWave isn't a general solution, sure. But mmWave is great for anywhere crowded enough to benefit from a DAS setup, and there are a lot of DAS setups around.
Any place outside, in good weather, with high population density!