It seems to me that there is too much emphasis placed on ESR. People build and buy devices to measure it and then scratch their heads while asking about the results of measurement.
In general, ESR is higher when a capacitor has questionable termination. This may be due to previously excessive current flow, or mechanical damage. Other than those two, there are few reasons a capacitor will measure too high an ESR. And what is too high? That depends on the circuit in which it's used.
Leakage is also a concern, and ESR meters don't measure it.
The capacitance is usually the important parameter. ESL is important too and, like ESR, has to do with capacitor termination and design.
When designing a circuit, ESR can be important, so you decide just how important, and use a capacitor that takes care of it. Other than that, it's not a particularly important parameter to measure.
So the question arises, is this test being run to evaluate a capacitor for a given design, or is it being run to see if a particular capacitor is good?
Like most rules of thumb, the numbers you get may or may not be significant. It depends on the application.
I have measured capacitors over a wide frequency range, and most of them are not even still capacitors at high enough frequency. The worst offenders are aluminum electrolytic capacitors, which cease to be capacitive as the high end of the audio range is approached.
As I have said many times, there is no substitute for understanding the physics and knowing just what you want. Test equipment, like your fingers, are just tools and shouldn't be decision makers without consulting one's brain.
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