Emojis have become a communication method these days. People use emojis to make their chats look attractive, connecting and add more value to the sentence.
There is no specific reason to justify the yellow colour of most of the emojis, although some of them are of different colours also, but people on the Quora website have answered it:
Yellow emojis match our skin tone which makes them a relatable symbol for identity.
One user wrote, When we smile or laugh, our faces appear yellowish, which inspired the colour choice for emojis.
Yellow is a bright colour that shows facial details clearly, making it perfect for emojis to convey emotions.
Yellow represents happiness and positivity, making it a fitting colour for emojis.
Yellow stands out against black or white text, making it a practical choice for emojis in digital communication.