I think the general assumption is that QFT is true, it is just whether you can call the physics it creates as being particles. At least that is how I interpret

I think the general assumption is that QFT is true, it is just whether you can call the physics it creates as being particles. At least that is how I interpret it. QFT is QM, but it just has a lot more degrees of freedom (infinite) than what you are talking here about when you say QM. You can write a Schroedinger's equation for a field. Rather than the wave function being a function of X, the wave function is a function of F(X) where F(x) is a field configuration over space. I would say some of his argument comes down to semantics because by his definition in order for something to be a particle it can't have spatial extent. I think a lot of people don't include this in the definition of a particle. They do associate the number of "Quanta" with the number of particles, at least in a field theory. What I was saying above is that I believe you can create an object by the "Quanta" definition in QFT that has no spatial extent. His argument is based on the fact that this is not possible. Adding these Quanta together to form a zero extent object is similar to saying in Fourier analysis you can take a number of different frequencies (like the quanta at different wave lengths) and create a delta function (which has no spatial extent). The thing is, even though we are dealing with adding a bunch of frequencies together, it is not exactly the same as a Fourier series because we are adding them together in a different way. You make a good point about people first teaching the simple Schroedinger's equation of particles because it is a lot easier. I think what is so hard about quantum mechanics is relating it to the real world, and not the axioms themselves. The simple form is much easier to relate to the real world.