The cynic side of me thinks Google has figured this out:

- search history of more than 3 months ago is somewhat worthless for analytics/advertisement purposes;

- search history of more than 18 months ago is really worthless, but hey, we can also keep those just because we can.

fortunately they are just changing defaults. I worried i was losing all my location history, but just checked and it's still set to never delete.

I came here to write this exact comment but you beat me to it. They have just figured out that 18 months of your data is all they need to make you a monetisable product.

What does "delete" mean? Does it mean that they remove the information from my account, or that they entirely remove all traces of the data and anything derived from it?

a very good point and something that will never discussed as it gets into threatening Google's core business.

This is meant to be PR statements to try and prepare for increased scrutiny and data privacy they see on the horizon.

This is, imo, meant to be a way for them to tell the masses "look we automatically delete you data!", expecting them to not have any understanding of models that can be built from the underlying data.

Unfortunately, the tech press will cover this at face value praising Google, as their livlihoods are all dependent on Google Ads / YT and free services like AMP.

Good point. Maybe it means "only we can see this data from now on, instead of the user, and/or our contractors and partners"

How about an option to delete everything right now? I think these "privacy" initiatives are as dishonest as they can be.

You can.

https://myactivity.google.com/myactivity It's on the hamburger menu

...and so young Raxxorrax set off into Google's vast, dark labyrinth of Privacy Settings, never to be seen again.

You can set up automatically