Fats are good for joints and hormone/lipid production. I'm not a fan of low protein, low fat, high carb. With bulking, I am more a fan of increasing fat and protein intake and maybe, slightly increasing carbs.
Every time my weight gained stalled, I upped my fat and protein content and my gains would restart again. Swapped steak for chicken, increased almonds, and more olive oil and butter. Lather, rinse, repeat.
That email is why guys are rails and not tanks.
People need to stop it with the "science" of macros and focus more on the "simple math" of calories in versus calories out. Especially when they want to get huge. If you are cutting, different story. But this is a guy trying to bulk.
Complication makes it easy to explain failure.