Antibiotics, and bacteriophage viruses, kinda are nanotechnology (albeit in the same limited sense that steel dates back a thousand years).

You might like bacteriophages — viruses which eat bacteria: https://en.wikipedia.org/wiki/Bacteriophage

Kurzgesagt has a cool video on phages. But I meant the grey goo kind of nanobot

We are the goo ;) (I want to finish that “goo gatchoo”, musical puns aside, we are what grey goo is capable of and what it ends up looking like).

Interesting idea, never considered that angle. Perhaps I should clarify that like my goo to obey commands written in ACGT, and not some future kind using C