Be mindful of cultural trends and retconing your own mind. Nanobots (or nanites, or nano-tech) is a trope that came much later in cinema.
That trend was definitely influenced by some T3 stuff, however, in T3 terms, the Terminatrix is still bound by the more general idea of mimetic polyalloy.
Therefore, we can't say T3 uses nanobots.
Also, be mindful of nuanced representations of technology in movies. What we perceive to be robots, often, are not meant to be taken as that. They instead represent a general concept, often materialized into a character.
For T2, that concept is a clash between counter-culture (represented by the T-800) and state opression (represented by T1000), roughly. In the real world, both movements are artificial inserts into the collective consciousness. It's not as clear cut as I'm explaining, and there are other superimposing representations on top of it, but it should be enough to get the idea.
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The impression I get, is that you're waiting for me to explain that T3 is actually a story of us running into disaster, and you have some sort of expectation in regards to how I would do that. If that's the case, I'm sorry to disappoint you!