Well, I believe that there was an intention of checking that the column would contain valid values and that the table was actually working correctly.
Without checking values, the table could be showing garbage.
That been said, obviously the issues is that the test doesn't adapt to the system it's run on, so the only other two ways I see which give more value to test is to retrieve that information from another "more reputable" source (system commands), accepting it as the "truth" and checking it against the table results.
This is the only way to have the test adapt to the system it's run on and test almost the whole pipeline.
The other way (but we lack the framework), would've just been to fake what the table is using to extract this information, so that it would receive a controlled set of values that we could later check.