Impossible to answer such a broad question without knowing specifics of that particular situation, as it is heavily dependent on the person's pay/career trajectory at Google (which, from my experience, can differ wildly even for the same levels), spending habits, how they invested what they haven't spent, their family situation (single? married with 2 kids? supporting parents?), how much debt they had prior to joining and how fast they paid it off, etc.
It can be anything from "multiple houses, cars, quickly growing investment portfolio, and etc." to "barely anything aside from a few months worth of salary in the savings account". The latter seems extremely unlikely though, most people hover somewhere in-between those two extremes.
For example, look at some engineers who worked at Google's self-driving division/Waymo. From the court papers (from that trial where the lead was accused of taking the proprietary info to Uber's self-driving division), it was mentioned that some of them got paid like $10mil/yr. This is in a completely different ballpark, compared to what most of engineers at Google make. Just goes to show the wild variation in pay, which makes it difficult to estimate without knowing the details.
