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.
Oh you sweet summer earthling. He doesn’t even know about Quasithought Injection yet
God dammit Steve! Stop trying to help the humans. Theyre boring, now let’s go home, this vacation sucks.
Futurama did it. Was used for ads