What they are saying certainly makes a lot of sense, when you think about the mechanics behind a grasshopper being able to fly, versus a … fly.

Insect-scale robots face two major locomotive challenges: constrained energetics and large obstacles that far exceed their size. Terrestrial locomotion is efficient yet mostly limited to flat surfaces. In contrast, flight is versatile for overcoming obstacles but requires high power to stay aloft. Here, we present a hopping design that combines a subgram flapping-wing robot with a telescopic leg. Our robot can hop continuously while controlling jump height and frequency in the range of 1.5 to 20 centimeters and 2 to 8.4 hertz. The robot can follow positional set points, overcome tall obstacles, and traverse challenging surfaces. It can also hop on a dynamically rotating plane, recover from strong collisions, and perform somersaults. Compared to flight, this design reduces power consumption by 64 percent and increases payload by 10 times.

I wrote about this briefly back in 2018, in reference to 1970s research, given the challenges with insect-sized flying robots.

The Insectothopter was plagued by inability to fly in actual weather, as even the slightest breeze would render it useless.