It's really palpable, developers in these orgs just stopped caring about the quality of their work.
Each one of these distractions can blow the mental context of a developer for hours as well - so not only do they get very, very little time to actually "program" - but the time they do get, is now mostly trying to get back into "flow" , re-establish a full mental context of the project, etc... So - that 5% is likely a huge over-estimate of the amount of "productive" time a developer has, as a good chunk of that is just recovering from the bullshit that the company inflicts on them so they can go heads down and actually start doing "work" - realistically I bet if you watched your average developer at a big FAANG - they spend substantially less than 2% of their time actually heads down coding productively.
So - definitely agree with your general thesis.