I agree that hydrogen in airplanes has some potential, though there are certainly issues - you need cryogenic cooling to avoid super heavy pressure vessels, and if it fails..., but there are similar fuels that could work.

As far as disruption, the issue is that there is no opportunity for competition. Countries are rabidly protectionist about their airplane industries, and any newcomer even with a completely superior product (See: Bombardier C-Series) will get absolutely destroyed by sanctions, tarrifs, or even secondary export controls (Gripen, Avro Arrow, etc...). You cannot succeed unless you are American, and even in America Boeing has massive undue influence.

All true. I do think there is a window to succeed in the U.S. In Europe it's just much harder to innovate more generally.

Also the SAFs are looking pretty good. Point is, I don't think we should decide that planes are bad of all sudden, that doesn't seem like a very wise thing to do given the massive benefits of air travel. Rail is also great but rail shines for cargo and large volume traffic between urban cores

One of the fields that isn't true is civilian aerospace. Innovation cycles are long, regardless of country, regulations are more or less the same. Nobody only certifies according to EASA or FAA, everyone does both. And with Airbus and Boeing forming a duopoloy on civilian aircraft, both sides have equal interest, and funding, for innovation.

Throw in all the current eVtol start-ups and I don't see that much difference between the US and Europe.

Airbus and Boeing have plenty of competition in the smaller jet range: Embraer, Comac, Sukhoi, until recently Bombardier. If it was easily to scale up, it would have happened by now.

I do agree that an electric/hydrogen jet is the kind of disruptive tech that could upend the market, but due to the long lead times, stringent certification and very political markets it's an arguably even tougher market than cars or rockets.

Bombardier Aviation was bought by Airbus, Embraer almost by Boeing. Funny enough, there was always a lot more competition in the regional market then for bigger single aisle planes (B737 and A320).