So basically it's a gas canister filled with hydrogen instead of propane gas (which, by the way, is available almost everywhere at least in the US). It seems that they might have implemented a "quick" swap locking mechanism but that's pretty much it.

What I am wondering is:

1. How is this different than just using H2 canisters that are already available for welding (for example)? I wouldn't want to do a "hot swap" for a gas tank in a car as there are a ton of things that can go wrong, but that's pretty much what these canisters are trying to do anyways.

2. For home use, big propane tanks are already commonly used in places where there is no municipal natural gas line, so why would someone use theses small canisters instead of just installing a big tank for hydrogen outside?

3. Isn't the energy density of H2 way lower than other gases that could be used for automotive purposes? For example, in Europe is common to have after market conversions to propane or natural gas. Both have more energy density than hydrogen, leading to either smaller/lighter tanks and/or higher range with the same volume of gas. I get that hydrogen has the potential to be green with electrolysis (but we are not there yet and most H2 available now is made from hydrocarbons anyways) but it seems to be trying to be solving a problem in a convoluted way and/or mimicking the "electric battery" hot swap technology but for hydrogen without getting complete tech parity with it.