Liquid hydrogen is the only viable carbon neutral fuel source for air travel due to its energy density. Reducing weight is the #1 most important factor in building aircraft. This shouldn’t come as a surprise. It’s common sense. Hydrogen can be produced via electrolysis, whether you want to whine about the current situation with natural gas based production or not. It is the only option we know about that is capable of addressing the issue of carbon emissions from air transport. Unfortunately, liquid hydrogen much less energy dense than kerosene, but it’s all we have. The important part is that hydrogen is a clean fuel source which can be produced via clean energy.

Unless you have a Nobel Prize winning alternative energy solution in mind to power aircraft with zero carbon emissions with an energy density as good or better than liquid hydrogen, your advocacy against its use is an impediment to progress.