What scares me about all of this is that so far nobody has faced any real consequences except for the whistleblowers, and Boing doesn't seem to suffer all that much.
Building airplanes is a near-monopoly market. It's also a market where few units are sold (compared with, say, smartphones or virtually any other consumer and most industrial goods). That means you can pull stunts like low priority on quality, because you can make the probability calculations and they can end up in your favor. If cutting costs on corner X has a 1 in 10,000 chance to go wrong, in smartphones that means there will be hundreds of failures and your chance of getting away with it without headlines or class-action lawsuits is pretty slim. But if you only ever sell a few hundred or so - even the highly successful 747 has like 1500 units sold in total - then you have a very good chance that the 1:10,000 failure doesn't happen. So a business decision to just take the risk can make sense.
And if the industry and courts don't punish you, severely, the message is clear: It's ok to take these risky decisions.
If we don't want planes falling out of the sky, then the people making those decisions need to go to jail, and pay enough fines to wipe out a couple years of work, bonuses and all.
As someone who has worked with management on all levels, I'm convinced that wide-spread quality-is-a-low-priority attitudes like this don't happen without top management knowledge and at least tacit approval.