Google recently made a change in the way they handle sign-in for any Google website. What this new change brings into account is that now whenever a user signs in into any Google website, they are also signed in into Chrome with the same account and if the user signs out from that very Google website, they are completely signing off from out of their Google account. This new sign-in status is easily discernible as every new sign in shows their Google Account picture in the Chrome UI.
This will help the user keep track of which Google account is signed in and will also prevent them from mistakenly searching for something or browsing the website which could be visible to another synced account. This will become beneficiary for users who share a single device but uses different accounts for signing in to Google Chrome and its facilities. However, this new change does not mean that it triggers Chrome sync. If anyone wants to save their browsing histories or data or passwords available on other devices, they must keep in mind to turn on the sync manually.
Google values the feedback of its users and over the past couple of years, users who share a single device have expressed their confusion over this matter of signing-in from different accounts. Keeping those feedbacks in mind, Google has taken this step to make the change. Chrome 70 is scheduled to be released mid-October and Google is going to make these updates in that upcoming version.
Google is extra precaution with this new change. Chrome 70 also adds a control which allows the users to turn off the feature which links website-based sign-in with browser-based sign-in. Google is looking into the way they handle the clearing of auth cookies. Google wants to implement a feature which will delete all the auth cookies when the user signs out of that website.