While pet insurance companies operate on their own policies and procedures, at this point in time (2023), the answer is NO.
Because genetic testing is prognostic, not diagnostic, an at-risk result does not indicate a preexisting condition. There is never a guarantee of diagnosis based on a result and only veterinarians diagnose disease.
Furthermore, because we know breed can impact disease underpinnings, there can be varying levels of penetrance, as well as other factors such as lifestyle and unknown genetic variants. Insurance companies will not take Embark results provided as a diagnosis.
An interesting side note to also consider is genetic testing can often drive interest in pet insurance. If a genetic variant is found to be present in a result, pet insurance is often considered to better prepare for what may or may not arise down the road. This ultimately leads to a better quality of life for both the pet and the owner.