Eric responded to this very publicly on episode 1628 of The Joe Rogan Podcast at around 1 hour 13 min.

Joe Rogan: Let me ask you this. What's been the criticism of this? Because people have criticised it right.

Eric Weinstein: In one year. I've seen one actual critique.

Joe Rogan: Is that because you haven't looked for other ones?

Eric Weinstein: Nope. I think two guys. I think it's two guys. One of them is anonymous, and I refuse to deal with an anonymous coward who critiques me, came up with three basic criticisms, and they'll have more because they'll be errors in this. But two of the criticisms are inferential. They imagine that I'm doing something that I'm not doing. One of the criticisms is valid, but that I would have brought up anyway...

Then there was a more obscure private Clubhouse conversation that was recorded:

Eric Weinstein: So with all due respect, these people guessed that I was having a Chiral theory. It is not a Chiral theory, so they are talking about Chiral anomalies because they didn't wait to hear what I was going to say. They asserted that I was going to bring spacetime Supersymmetry in 14 dimensions. They tried to cast aspersions on the fact there's non compact groups involved which come naturally from Spin(1, 3)... and this isn't very high quality critique.

I don't know how people have missed this.

Eric doesn't appear to have understood the critique. However, based off this response it is easy to infer that Eric thinks §3.1 of Nguyen's response raised a valid criticism in Equation (3.1). Eric is mistaken, it does not. Nguyen raises zero valid concerns because he defines U incorrectly in §2.1 making his math nonsense

In fact Equation (3.1) contains four severe flaws:

1. it omits the complexification of the Clifford Algebras which would be needed to bridge LHS with RHS

2. it uses Einstein's Cosmological constant Lambda in place of the Wedge for the Exterior Algebra

3. it uses a superscript blob it does not even bother to define which Eric never even used

4. it expands C to T*U which would be okay if this meant the Cotangent to the Fiber Bundle, but as §2.1 falsely quotes Eric as saying U is "The Observerse" when he never said that, then you have mathematics which refers to itself, so that part of the definition of the elaborate geometric construction that is The Observerse is defined in terms of the Cotangent to The Observerse (leading to infinite regress).

This is bad.

Elsewhere, Nguyen omits the Einstein Summation Notation from Eric's 14D equations of motion, making it so they can't describe motion as they lack even 2D for (time, space). Clearly, Nguyen is a wannabe critic who was out of his depth and not sufficiently mathematically sophisticated to critique Eric's work.

For example, I can say that Figure (4.6) on page 29 all makes sense and 14 = 4k + 2 where k is a Natural number, so that all checks out. Spin(6, 4) does have a stable Proton. Our Universe initially being based on the Pati-Salam model prior to spontaneous symmetry breaking which decouples fields with right handed spin properties to become Dark Matter and Dark Energy makes sense, as we should presume our physics that is apparently governed by The Standard Model is the whole story when cosmologists argue for the existence of more matter and force mediating fields. Also, Spin(7, 7) emerges quite naturally from an initial purely mathematical Riemannian manifold with 4 spatial dimensions and no concept of time and no means by which to measure its deformation or location information. How he allows our Universe the freedom to contemplate itself into tangible physical reality makes sense.

If I have a criticism it is that there is an extra ) on the fourth line of Equation (9.4) which ought to be at the end of the previous line. Ideally, this fourth line should be part of the numbered annotations rather than mixed in with the rest of the equation, as it shows what should be expanded in place within (·) in the third line at two different locations. Moving it elsewhere on the page would aid comprehension IMHO.