I'm not in that area, but I struggle to find an analogue of a large pressurized tank on Earth where mass is the dominant cost factor.
You might have equally big tanks on Earth, under equal pressures, but it will be more cost-effective to just increase the material used on the shell of the tank to solve your problems. Whereas in space, every kg that can theoretically be removed from the launch vehicle is worth investing in, even if it raises the cost of engineering and materials.
So yes it seems reasonable to me that these are groundbreaking challenges.
You might have equally big tanks on Earth, under equal pressures, but it will be more cost-effective to just increase the material used on the shell of the tank to solve your problems. Whereas in space, every kg that can theoretically be removed from the launch vehicle is worth investing in, even if it raises the cost of engineering and materials.
So yes it seems reasonable to me that these are groundbreaking challenges.