Google are going to reverse this in Chrome 70 - https://www.blog.google/products/chrome/product-updates-based-your-feedback/
I find this behaviour weird - if I want to clear all cookies, I'm explicitly asking it to clear ALL cookies including Google ones, so I expect to be logged out of everything. What issue did they think they were solving by keeping Google cookies persistent?
If they want to give the option of the user keeping Google cookies persistent while deleting everything else, they simply need to produce a better cookie deletion interface that lets people delete individual groups of cookies instead of users having to rely on the Inspector to do it.
Biting the hand that feeds IT
