Now you are going to start a nerdy discussion whether Link really can’t talk, doesn’t want or like to talk or does indeed talk, even though not directly shown usually in the games.

There is plenty of reason to assume that he actually can talk fine, it was just omitted for convenience or immersion in the games. It was implied often by the dialogues thoughout various games.

Official mangas show him talking, dialogue options, or that e.g. Zelda learns Links name when asking him in OoT imply this as well.