Do high-DIAAS proteins build more muscle?
Not automatically. A high DIAAS means a protein source is strong at supplying digestible indispensable amino acids. That is useful, but muscle gain still requires enough total protein, enough calories (or at least not too severe a deficit), progressive training, and recovery.
Eggs, dairy, meat, and many isolated proteins tend to score well on protein-quality measures. Many plant proteins score lower as single foods because one indispensable amino acid may be limiting, but that does not make plant-based diets ineffective. It means dose, variety, processing, and protein pairing matter more.
For muscle gain, use protein quality as a planning tool, not as a magic ranking of foods. If you regularly hit your total protein target with several high-quality meals, the difference between egg, beef, whey, chicken, Greek yogurt, and a well-planned plant protein meal is usually less important than training execution and consistency.