Is it a good idea to use Emojis as icon pack on web?

Since Emojis are basically Unicode characters under the hood they don't take space like any image or vector.

I see here an opportunity to keep the bundle size smaller for my web app.

Example use case: Country Flags

Instead of downloading county flags and adding them to the project, using emoji county flags sounds good.

Is it a good idea to use emojis as an icon pack on the web?