Cryo/pressurized storage isn't technically necessary for ships either. Liquid hydrogen with insulated storage works well enough. The key is evaporation rates. A

Cryo/pressurized storage isn't technically necessary for ships either. Liquid hydrogen with insulated storage works well enough. The key is evaporation rates. As long as the ship consumes fuel faster than it evaporates, there is no need to maintain pressurization. In practice, some buffering pressurization may be necessary, but the scale of pressurization needs will be a lot lower than is required to store hydrogen long term.