I guess unless you are a welder, a scuba diver, or work with liquid gasses, very few people study compressed gasses.
The expansion ratio of liquid hydrogen to gas is 1:850 so liquid hydrogen is very compact compared to atmospheric hydrogen. Also very heavy with the insulated containers, etc. https://en.wikipedia.org/wiki/...
Unfortunately the subject got a little confused when the energy density of compressed hydrogen was not shown. It has an energy density of 7 MJ/L. And because most hydrogen is compressed and stored at 700 bar (~10,000 psi) it means the storage is only about four times as large as AvGas, but compressed gas is much lighter than a liquid. Cars, busses, and some garbage trucks all run just fine using compressed hydrogen, but they don't have as much worry about weight as aircraft.
This is where I get lost in the relative benefits of weight, volume, energy density, fuel efficiency (turbine engine at -60 degrees at altitude) of aerosol jet fuel vs gaseous hydrogen, and so on. I just assume people smarter than me think it is worth studying.
(In a "Look! A squirrel" moment, liquid water to gaseous water (steam) is 1:1700. That is why steam was such a powerful power source and steam condensing back into a liquid can leave a large vacuum which may cause containers to crush from atmospheric pressure. Too many YT videos showing soda cans, 55 gallon drums, and train tank cars imploding to mention.)