Structurally they are similar enough that we can communicate. The discovery would be altering our science, but every attempt to exchange beyond technicalities and niceties is somehow incredibly boring to both sides.
After the initial awe, it would be like, yeah, we know aliens.
Bold accusation.
Sure it would be mind-blowing, but society-wide awe about other(ed) societies on this planet has largely waned off and many people do not care about the lives of people deemed other.