Google is not only a commercial company, but also a convenient international service for intelligently storing data about users and their needs.
Compared to Mail, in my opinion, this is a larger-scale system that covers many of the subtleties of working with the user, including taking into account Personal Data Laws.

When we talk about profiles on social networks, it is important to emphasize that this is necessary for:

• Keep apps and sites you visit in sync
• Organize your contact list, keys and passwords. So as not to get confused and not come up with 0 every time
• Payment services understand you perfectly, because you can optimize bank cards

Authentication allows the system to recognize you and not ask you for a password every time. This is where a Google account comes in handy.
Indicate in the phone/mail settings what you have access to. You won’t have to open it every time, but the system will keep you in mind.

The design and internal structure of Google services gives you the right to provide access to you to different people:

1. You can create a storage with the amount of memory you need and define access settings
2. Customize the visual for yourself and your audience

Accounts include mail, your devices, your personal data and locations. It's convenient. It would be good not to keep all the details of these decisions in your head, but to trust one provider, as I do.