The planes were built fine for their purpose which did not include a single trip (at the very least they wanted to bring their crews home because those are as hard or harder to replace than the planes they fly!)and of course they're rougher than civilian planes nearly a century on all military transport and fighting craft are going to feel crappy compared to the civilian accepted version.

They selling tickets at our nearby Air Zoo for a 30-minute ride in a WW2 bomber. They're (intentionally) underpriced at $200, they sell out fast, so you have to plan the trip well in advance.

The "average HN reader", even one who advocates for wearing seatbelts on passenger planes after the recent London flight tragedy, likely does a dozen things a week that are more dangerous than riding in an antique plane.

That's not how they were built. The crews cost far more than the than the planes, on multiple axes.

Chances that China is starting to build pretend-planes to be used as bombers for South-East Asia?

Maybe.

But you[re missing the point.

How many 'good enough' planes could we build in 5 years starting now, if we needed to?