I think that's a little too simplistic. They would not be the world leading fab without ASML. ASML's EUV process may be the most complex piece of machinery man has ever created.
It's maybe more like ASML's machines are like a Stradivarius, and TSMC is the best in the world at playing the instrument.
ASML makes the film.
Zeiss makes the cameras.
TSMC is the movie studio. They'd be making hit movies no matter who was supplying the film and the cameras.