> our existence now is so unlikely that it's possible that we actually are the first. Something has to be first.
When the OP said that ^ I took we to mean humans with technology, presuming the OP meant that we were somehow special. Basically I took it as him saying that we're first because we're lucky so my argument was:
> How are we lucky? Look at all the other intelligent lifeforms on Earth! Surely the lucky winners would have had some sort of fluke that made them one of the few with intelligent brains on their planet! This could have easily happened sooner on Earth!
If the OP meant that life itself was extraordinarily rare on any given celestial object then that is something I don't consider especially groundbreaking since its part of the Fermi Paradox formula in its basic form the precise value of which has been debated for years and I do not find convincing.
I don't quite understand your logic here? The big barrier(s) doesn't seem to be tool use, but rather 1) the formation of life itself, and then 2) the move from single-celled organisms to multicellular organisms (this took 2 billion years on earth, so is clearly a very difficult step).