I'm more interested in seeing what conditions the parent stock might carry. So I think whenever possible genetic testing is a good thing. It's quite reasonable these days.
https://www.vet.cornell.edu/departm...ealth-information/benefits-canine-dna-testing
Knowing if a dog is a carrier for things like DM, or the MDR1 gene can help me be prepared, or again choose not to get a dog from that breeder. I personally don't get breeds where hips and elbows are important, but if I was getting a lab, golden, or definitely a German shepherd it would be helpful to know where the parents are. It doesn't guarantee anything, but it might make me choose another breeder based on the results.
That being said, it isn't a deal breaker for me personally. I've gotten many dogs over the years way before all the testing was done, and it hasn't been an issue. I guess it depends what's important to a person.