The world should just slow down and go with all electric planes.

Very cool.

Some variants of the AT-6 trainer aircraft from WWII used direct drive engines that pushed their prop tips supersonic. I saw a gaggle of them flying at an airshow once and the only things that got shaken apart were my inner ears. I loved it.

Propeller tips routinely go transonic. The shaking of WW II fighters in a dive was due to early transitions on the airframe, as described in the rest of the article.

It's a good thing fuel consumption is predicted to be 70 lower as those ultra-thin wings and trusses will not hold much.

Wouldn't extra long wings make things harder at airports? How about biplane approach instead (with shorter wings)? (It could be vertical (one set of wings on top of the other), or, horizontal (one set of wings behind the other)!)

Yeah, let's cut the range way down while decreasing the payload at the same time by going all electric! Oh yeah, that makes PLENTY of sense! And those batteries aren't made from any exotic materials now, are they? Just easy to come by stuff that you can buy at any Walmart that don't require lots of energy to refine and then reform into something usable? Uh huh, I don't see any downsides at all to converting ALL modes of transportation to electric drive! Why didn't somebody think of this sooner? There's no reason at all for ever using petroleum products as a fuel source!

Boeing is not unfamiliar with wing design. The longer a single, straight trailing edge is, the more efficient a wing is. Multiple wings tend to interfere with each other at high speeds. I'm surprised that Boeing accepted the drag and lift penalty the lower truss has..

Expanded, is aluminum exotic? As Alum/air batteries have the effective density of jet fuel when you take efficiency into account. Several other chemistries are coming too. Zinc/air is already here. And so much safer than filled with Jet fuel. Same for shipping, taking on some containers of batteries to power the trip. While I like the concept aircraft, a longer cord and less wingspan with good wingtips could do as well on the wing. While thin wings look lighter, they are heavier to make.

Yeah, like there's no penalty to continuing to burn fossil fuels for as long as we can still shake the ground apart and pollute the aquifer in our efforts to extract them.
Seems to me like someone needs an expanded viewpoint.