This is the information they provided:

About linked services
Google currently shares data across its services for the purposes described in its Privacy Policy at g.co/privacypolicy, and depending on the previous choices that you've made about your privacy settings, such as Web and App Activity, YouTube History and personalised ads.

As of 6 March 2024, new laws in Europe will require Google to get your consent to link certain services if you want them to continue to share data with each other and other Google services as they do today. For example, linked Google services might work together to help personalise your content and ads, depending on your settings.

Services you can choose to link
You can choose which services to link from this list of Google services:

Search
YouTube
Google Play
Ad services
Chrome
Google Shopping
Google Maps
All other Google services that are not listed here are always linked and therefore able to share data with each other for the purposes described in our Privacy Policy, depending on your privacy settings

What data is used
Personal data that is collected about your interaction with Google services can be shared across any linked services. This includes:

Searches
Videos you watch on YouTube
Apps you install from Google Play
Associated info, such as your device info
All the other types of info described in our Privacy Policy
How Google uses this data
Google uses data shared across linked services for all the purposes that are set out in our privacy policy:

Providing personalised services, including content and ads, depending on your privacy settings
Maintaining and improving our services
Developing new services
Understanding how people use our services to ensure and improve the performance of our services
Performing other purposes described in our privacy policy
What won’t be affected
The choices you make about linked services will not change:

The purposes for which Google uses data
Your privacy settings, such as choices you have made about personalising Google services
Aspects of a service that don’t involve sharing data
The following can always be shared across Google services:

Info that’s associated with your Google Account and not specific to any service, such as your profile picture or the info used to verify your identity
Content or info you’ve chosen to make publicly available on Google services, such as comments you’ve posted on YouTube
Your data from all Google services, regardless of whether they are linked, may still be shared across all services for certain purposes, like preventing fraud, protecting against spam and abuse, and complying with the law.

Your data may also be shared across Google services to effectively help you complete tasks when two services are offered together. For example, if you make a purchase on Google Play, Play and Google Payments will share related info so that you can complete your purchase.

Things you should know
Other settings let you control whether you see personalised content or ads. Linking Google services is not about sharing your data with third-party services.

If services aren’t linked, some features that involve sharing data across Google services will be limited. For example, if you have personalisation on for a service in your privacy settings but don’t link that service, you won’t get personalisation based on data from other services, but can still get personalisation based on data from that service.

You won’t be signed out of any Google services if you choose not to link services.

How to manage linked services
You can manage your choices, including selecting other Google services to keep linked or withdrawing your consent, in your Google Account at myaccount.google.com/linked-services. You can also manage your other settings, like Web & App Activity, YouTube History and personalised ads, in your Google Account.