Yay we see the same on SAF, I couldn't agree more.
You'll probably guess I've spent quite a lot of time looking at hydrogen, including all the academic references I've been able to find on it.
All of them show signs of being biased, with some gaping great holes in what is known about it, despite some scientists spending their whole working careers working on it.
There appears no justification for why the area of the state change curves known about hydrogen go nowhere near the area we should be most interested in investigating for the purposes of liquefaction at room temperature.
The only equipment needed, to at least establish data around that area, even if it does turn out to be phsyically incompressible to liquid at room temperature, is a large block, small bore, long travel ram, made from stainless steel, with plunger machined to near gastight fit with the bore of the block, and maybe a valve at the end to release liquid if the gas goes to liquid, to a much lower pressure chamber, where liquid could be shown to be collected.
A pressure sensor on the ram would then chart the temperature vs displacement curve of the system. The volume of stainless steel around the bore would keep the bore at more or less room temperature, if the compression stroke made at slow speed, and the material of stainless steel is known to contain hydrogen at pretty much any pressure, because we know that as the density of hydrogen goes up, it passes a point of being able to penetrate materials, not even up the sides of the piston, after a certain compression is reached, beyond this it is more or less fully contained, so in theory we should be able to compress it not only to a liquid, but even to a solid.
From the beheviour of other gases liquidised, its a reasonable bet that it would stay liquid under modest pressures, like butane or maybe a little higher, but not requiring thick skinned pressure vessels to contain it, like it does when just pressurised as gas.
To me, as someone involved in a lot of ground breaking industrial research work previously, I don't see any reason this can't be done, other than the obvious anti-funding forces opposing it.
