Totally agree. The TX was way, way less advanced than the T-1000.
While I whisked away a couple of hours reading that incredibly astute in-depth critique of T3 that you led me to, a-dev, it got me wondering if perhaps sexism was, in some small way, involved in just how pathetic & inept the TX was handled.
I mean, Arnie is quite openly sexist & I can just imagine that back in the day when he found out that this new Terminator was being portrayed by a woman that he would then demand that she 'in no way' gets the better of him in any of the fight scenes. That character, surely, couldn't have been written that piss poorly on paper, could it? You'd think that the writers must've originally come up with a Terminator that they thought was much more powerful than a T-1000 but, hey, who knows.
The simple fact is that the one we saw on screen was, for me, truly one of the most unintentionally comically inept villains in the history of cinema.