Remember, the bigger the cap, the lower the ESR.
(Though it's a factor of both the capacitance AND the voltage rating. So you can't compare apples to apples if they are different voltage ratings.)
My experience with caps is they're typically ok, or they are REALLY not. (Like either leaking, or the ESR will be 10/20/50x what you expect, if not more.) And/or they just won't be filtering, in which case you get very high ripple. But for anything except the smallest caps (<10uF), if I throw the ESR meter on there and get something under an ohm, they're fine.
And the larger the cap, the less likely it is to be bad. So I really only take notice on small caps, if you get measurements of 10 ohms or more. When you do find bad ones, it's usually the small ones that are also lower-tier or unknown brands. It's really not that common to find 470uF or bigger caps with high ESR. Not impossible, but not anywhere as common as bad 1/4.7/10uF's.