overall, reasonable points

I disagree. I think it's a paper which looks backwards in an unconstructive way. The author is hoping for conceptual breakthroughs as good as relativity and quantum theory, but which don't require engagement with the technical complexities of string theory or the Standard Model. Those two constructions respectively define the true theoretical and empirical frontier, but instead the author wants to ignore all that, linger at about a 1930s conceptual level, and look for another way.

ETA: As an example of not understanding contemporary developments, see his final section, where he says

While string theory has extensively studied how the interactions in the hydrogen atom can be represented in terms of the string formalism, I wonder how string theory would answer a much simpler question – what should be the electron in the ground state of the hydrogen atom in order that the hydrogen atom does not possess a dipole moment in that state?

I don't know what significance this question has for the author, but so far as I know, the hydrogen atom has no dipole moment in its ground state because the wavefunction is spherically symmetric. This will still be true in string theory. The hydrogen atom exists on a scale where the strings can be approximated by point particles. I suspect the author is thinking that because strings are extended objects they have dipole moments; but it's not of a magnitude to be relevant at the atomic scale.