It's useful for grid storage. Very large amounts of hydrogen are already stored in salt domes[0]. Current salt domes have volumes in the range of hundreds of cubic kilometers and can support pressures around 50-150 bar, translating into storage of thousands of tons of hydrogen. Along the texas gulf coast, there are hydrogen storage facilities that each store enough hydrogen to translate to around 100 GWh chemical energy. Being able to convert that chemical energy with 40% end to end efficiency means one site could store 40 GWh. In comparison, in 2023 the entire world had only around 56-200 GWh of battery storage capacity[1] installed.

[0]https://energnet.eu/wp-content/uploads/2021/02/3-Hevin-Under... [1]https://www.rethinkx.com/blog/where-is-all-the-battery-stora...