That supposes Earth is special and deserves a particular treatment.
It seems likelier that we are too far from interstellar civilisations to be visited by them, or that there's no interstellar civilisations because of a Great Filter, or even simply that earth is not interesting enough for them to visit. Or worse, they do visit, but the human race is not interesting enough for them to make their presence known to it.
True. We haven't confirmed a single other one yet, which is why actually finding one will be probably the most significant discovery humans ever make.
But I would imagine that an interstellar civilization that has discovered thousands of life-bearing planets would start to develop some criteria about what type of life is interesting or not. It could just be that nothing on Earth meets the criteria to be interesting.
It seems likelier that we are too far from interstellar civilisations to be visited by them, or that there's no interstellar civilisations because of a Great Filter, or even simply that earth is not interesting enough for them to visit. Or worse, they do visit, but the human race is not interesting enough for them to make their presence known to it.