That's generally true, and the solution is to avoid linking them.

It's a rock-and-a-hard-place problem, since the most common scenario Google is dealing with is criminal enterprises trying to obfuscate their activity behind dozens of "independent" accounts (so of course they have to try unifying accounts). But this is analogous to the scenario one deals with separating concerns when forming an LLC; you keep your work and personal stuff separate, including finances and capital (i.e. don't do work stuff on your personal computer; that's riksing having your LLC status collapse if someone has occasion to sue you).