Flags for currency mostly work because nations choose their flag and choose their currency. Flags for languages doesn't work because it's common for the same language to be popular in different countries and for multiple languages to be popular within a single country.
ISO language abbreviations would be a better alternative than the flags but I don't think anything is needed at all; anyone who knows German will recognize the post titles written in German and anyone who doesn't know it will still recognize that they're not in English.
The links do have `hreflang="de"` which in theory can programmatically indicate the language used at the destination, I'm not sure there's any technology that takes advantage of that. They could use a ::before pseudo-element with content: attributes(hreflang) to display the ISO code instead of the flag images. I would like to see `lang="de"` attributes on the German headings and paragraphs on the home page, they would tell screen readers to switch to a voice appropriate for the language when read aloud.
Which flag would you use for euros? Obviously not the european union flag, since there are many countries inside the EU with a different currency (like Sweden or Poland) and even countries outside the EU whose currency is the euro (Montenegro, Kosovo, Andorra, ...).
Yeah, you're right. I did think EU membership was more aligned with use of the Euro (I only knew about the UK using the Pound but they're out). It's still true that each country chooses its currency but it would be just as weird to pick one country in the EU to represent Euros as picking one country to represent a language.
Same goes for Spanish. Which country's flag should represent it? Most people probably don't even know the flag of Spain and readers in Latin America might be offended.
I think the fact is that languages simply don't have visual symbols for them. They are spoken or written, not "looked at". Languages are linear, not 2-dimensional. Euros and Dollars have their symbol because that's what is printed on the 2D surface of bills.
ISO language abbreviations would be a better alternative than the flags but I don't think anything is needed at all; anyone who knows German will recognize the post titles written in German and anyone who doesn't know it will still recognize that they're not in English.
The links do have `hreflang="de"` which in theory can programmatically indicate the language used at the destination, I'm not sure there's any technology that takes advantage of that. They could use a ::before pseudo-element with content: attributes(hreflang) to display the ISO code instead of the flag images. I would like to see `lang="de"` attributes on the German headings and paragraphs on the home page, they would tell screen readers to switch to a voice appropriate for the language when read aloud.