One of the fatal flaws of self regulation is that it can be biased. The recent withholding of natural search data by Google feels that way. I'll break my argument up into 2 parts, the privacy perspective and the purse perspective ($).
According to Chromium blog, this change was implemented to combat malicious actors, here's their quote: "It helps ensure that malicious actors who might intercept people’s internet traffic can’t see their queries." However, there hasn't been action taken to hide these search queries when the referring source is a paid ad instead of a natural listing. To me, this assumes "malicious actors" either can't run ads or somehow the referring query is more secure for paid ads. I'm unaware of anything that makes the data any more secure or anonymous than its natural counterpart. So, we must be operating on the assumption that malicious actors are incapable of running paid ads.
Google is directly effected by withholding paid search data. Advertisers will no longer be able to analyze their accounts and optimize their ads performance. In most cases the difference would be astronomical if all query data were withheld.
Here are the industries/companies effected by withholding natural search data: recipients of traffic, SEOs, search retargeters. All 3 do not directly effect Google's revenue stream. In fact, SEOs often make Google's job of balancing algorithms more difficult, and search retargeters can be seen as direct competitors in the display space.
Its hard to think of these updates as fair or adequate when the company enforcing their self regulation seems to be acting only when its convenient to them.
Just my take on it until I'm shown why paid search data is any more secure or anonymous than natural data.