If I’m understanding your link drop correctly, I appreciate the sentiment, but my two thoughts on this are:

1. Countries are not languages, and vice-versa. There isn’t a 1:1 mapping. There’s a whole bunch of negative cultural and political identity nuances when people attempt to assign a flag to a language. For example, English is spoken far and wide, not only in England. Spanish is spoken in the Americas, not only in Spain.

2. There’s already emojis for country flags if somebody needs to add them to text!