[Someone1234]

After the blowback from auto sign-in they added an option to disable that on both Chrome and ChromeOS.

Settings -> Advanced -> Allow Chrome Sign-in

If you want even more control use ADMX (enterprise policies) to permanently disable it. For example on Windows visit Software\Policies\Google\Chrome\ in either HKLM or HKCU and set SyncDisabled 1, EnableSyncConsent 0, BrowserSignin 0.

Full list/docs:

https://www.chromium.org/administrators/policy-list-3

[benatkin]

I deal with it by having a separate google profile (“user”) and barely using it outside of gmail and google docs. I just let it sync.