NCCN and ACS guidelines support breast MRI >20% lifetime risk. So a woman has to beat the 20% threshold for lifetime risk as adjusted by her current age, correct?

Yes.  The intent of the guidelines was to look for younger women with a high long term risk, which is why they used lifetime risk.  This means that older women with a high short term risk but a low lifetime risk are not eligible. MRI eligibility by age.  Percent of...