Just to add. Looking at the current political state surrounding the Russian collusion investigation. It's not a stretch that Trump would not use this against his political enemies or "fake new media". And look at what his supporters have done with FBI agents that had an affair with private text messages. Trump isn't the first of his kind nor will s/he be the last.
IMO, they don't care enough to spot this. As long as deliverables are met, there is no incentive for them to dig around the roots. But I think once the "ponzi scheme" is exposed by having good talent refusing work in that toxic environment. shit gets really real, fast.
Although I'm not a fan of it. If you are doing "clever" coding. I urge fellow coders to please write some test cases for your "boring" programmers. Helps the rest of us to be brought up to speed and maintain it.
jQuery still exists. IMO, the ecosystem has just moved towards rich-client front end applications. There was no good tool/framework for that and people started fulfilling that need. Of course you could write like you said "unoptimized (or just plain horrible) code" which in an actual application is huge price to pay. I think it all boils down to being able to use the right tool for the job. I wouldn't advise using React or Angular to show static content e.g an splash page.
"Custom" framework.. idiosyncratic code. Code that is probably not properly documented, not properly vetted, or maintained as technology evolves. It is not to say it can't be done (e.g. fb, google, ms), but the cost of doing so greatly outweighs the benefits. For example, security concerns of your "custom" framework and onboarding of new engineering into your team. And are you really in the business fo "custom" framework?
IMO, Microsoft has the means and resources to sift thru linkedIn metadata to gain an hiring advantage over their competitors. In addition they could probably infer what other companies are doing thru their hiring and searches. There is no other platform like this with this scale another monopoly; human resources.