The argument that Hydrogen can't be used for aviation is now in dispute.  This eVTOL plane supposedly does 320 mph and has an 1150 mile range.  It flies at 21,000 feet, slightly under the 30,000 ft for most long flights bur still well above the weather in most cases.

It's Private Jet size for Billionaires, but I see no reason it wouldn't scale up for commercial passenger flights.  Actually, bigger planes have better volume/surface area ratio and can use heavier structural materials than smaller ones.

Calling it a "Jet" is a misnomer, because it uses electrically power fans, not direct propulsion from hot gas as a real jet engine does, but that's really irrelevant.  It flies at a fast enough speed to do NY-St Louis in under 3 hours and St.Louis-Denver in 2.5 hrs and Denver-LA 2.5 also.  So, 8 hrs, plus you don't need a landing strip.  The lack of sufficient range to do transatlantic and transpacific flights though makes its overall commercial viability outlook poor.  Looks like mainly a toy for billionaires.

I find this still to be questionable, because along with a dozen photos of the plane and 2 videos showing engineers in meetings, there was no video of the plane in action.  I also wonder how well all those little fans would work in a heavy rain?  BMW is a reputable companyy though, so that gives it a little extra credibility.

https://newatlas.com/aircraft/global-unveiling-sirius-ceo-jet-hydrogen-electric/

RE