I have the seeds of a theory that might explain this: this is the inevitable outcome of technological progress.

Like the American democratic system, Capitalism works best when all major parties involved in the system have comparable power and can keep the other in check. The major parties here are the capital class and the labor class, because Capitalism was conceptualized in an era when value creation could not happen without human labor. As such there was some measure of power available to workers, the logical extreme of which were such distasteful words like "unions" and "strikes". Nevertheless, earlier there was some balance and everyone benefitted (after that messy little Gilded Age affair was sorted out.)

However, technology, in the form of automation, has essentially been a force of labor displacement. Yes, we got amazing improvements in quality of life, but every advance also chipped away at the influence and power held by workers.

On the other side, the capital class have not been idle. Money attracts money... and power and influence. Capitalists have been using those levers to ensure most of the gains of technology accrue to themselves. Lobbying is of course the most obvious example, influence campaigns is another. But relevant to your post, another way this surfaces is the "so-called best practices" you mentioned. There is no "collusion" to suppress wages, just "best practices" of amorphous origins. Which somehow always benefit the shareholders. Funny that.

As you said this has been going on for a long time. But technology is amongst other things, an accelerant, and these trends have simply been amplified to become more noticeable.

And now there's GenAI, which is the ultimate accelerant.

Contrary to most media and HN, however, I think GenAI is not just the ultimate win for capitalists. If you think about it, by the same token(s) that GenAI disintermediates labor, it also disintermediates capital! (Who needs VCs when 1 - 2 motivated folks can launch ambititious projects with GenAI and public clouds?

GenAI is a unique opportunity to restore balance, and could actually be the thing that ushers in the post-Capitalism age... whatever that looks like.