It's a bit more complicated than that.
Good advice generally, particularly about time, energy and fees, but it's not necessarily 50:50.
As a general rule of thumb, yeah, in a lot of cases, it is indeed that simple. But there are exceptions, the most common scenario being when one spouse brings a vastly disproportionate share of the assets into the marriage. This is often the case in farming situations or where one party benefits from a large inheritance.
Imagine a scenario where a young lad inherits a 200 acre well stocked farm and swiftly follows his good fortune with a whirlwind courtship and brief and tempestuous, but childless, marriage. Do you seriously think the ex-spouse will walk away with 100 acres and half the stock?
Not gonna happen.