Two problems with that presentation:
1. The current theory that Alzheimer is due to accumulation of misfolded proteins in the brain was not confirmed in the latest trials of Alzheimer drugs that reduce those proteins but did not improve patients.
2. On one of the slides he shows that MTOR is coupled by eating lots of protein, which will reduce autophagy. That flies in the face of the carnivorous diet that is mostly protein, yet it reduces inflammation and improves health in many people.
My personal experience is that elimination of simple sugars (sugar, glucose, fructose, lactose) from my diet has an immunosuppressive effect - I stopped having arthritis aches in my hips, stopped limping, stopped having aches all over my legs, arms, and upper back, all due to immune hyperactivation. I get these symptoms back whenever I slip and eat simple sugars even in minimal quantities.
Note, that reducing inflammatory symptoms like in my example with not eating sugars is not "boosting your immune system" but suppressing it. For example if you have a headache from a viral infection, taking ibuprofen will kill the headache but will not "boost your immune system". Similarly, if you have an autoimmune disease, taking an immunosuppressant drug will reduce or eliminate your symptoms but that doesn't "boost your immune system". It just prevents it from activating. And lastly, cytokine storm by COVID-19 is treated by immunosuppressants - again the opposite of boosting your immune system.
Boosting your immune system is a completely different thing in medicine, not suppressing symptoms.