It might sound silly, but I really think this model should be replaced with the MW-2019 M4A1.
Let me explain, so far this m4 model in COD Mobile hasn't undergone major changes; they only slightly updated the sounds effects and added a new accessory (The grenade launcher) And… that was it. Currently, they haven't changed anything aesthetically, and it looks completely outdated in terms of model, texturas, sound effects, and accessories.
With the changes applied to the model and the design of the accessories, the weapon would be used a little more than it is at present ( I'm talking about the mesh, the texture, the weapon sound effects, but not the statistics), although a small seasonal buff wouldn't hurt
This might never reach the devs, but it would be great if the suggested change could be implemented.