I am reading this right?

Hi everyone,

I am not sure if I am reading this correctly so, I am looking for a second opinion. On this Google Guidelines link => https://developers.google.com/search/docs/appearance/site-names is saying that this URL structure for multilingual websites => https://example.com/de/index.html is not allowed? How is that possible there millions of websites using this url structure, I am sure missing something. What you guys think? Thank you!

Can you tell me in more details.

Google does recommend using hreflang tags and sitemaps to indicate language and regional targeting for your multilingual content. The specific guidelines you're reading might be referring to best practices for URL structure in the context of optimizing search visibility.