I understand what you are saying. But I was thinking more along the lines of what other games do. Things like Warframe, Paladins, Overwatch, and the like let's players tag walls and other objects in the game for fun. And in Warframe case a lot of the tags are player created things that have been approved by the devs themselves. It helps to ensure that no one can use the tags for ill will.
In some games players would tag walls and stuff to let other players know that they are guarding the area. If you are doing something like an area defense where you need to protect multiple places at once. Going around and checking what areas have tags and which ones don't is just a fast way to know what area is covered or not without having to wast time typing to people in chat. Even more so in game where a lot of stuff can be happening at once so people ignore the chat.
Also there are some games without a chat. Players can only talk using stickers and images. This a lots everyone to get basic ideas across without the need to understand other people's languages. For example, you know a powerful boss attack is about to happen and you want to warn your teammates in such a game. You just use the sticker of a character hiding behind a large shield blocking attacks. Although I mostly only see this being done in mobile games. With the only real limiting factor being how many different types of stickers their are can you string them together to get complex thoughts across if you wanted to.