Where is this explained? the article might be wrong then, because it does state the opposite:
scanning is now “voluntary” for individual EU states to decide upon
It makes it sound like it's each state/country the one deciding, and that the reason "companies can still be pressured to scan chats to avoid heavy fines or being blocked in the EU" was because of those countries forcing them.
Who's the one deciding what is needed to reduce “the risks of the of the chat app”? if it's each country the ones deciding this, then it's each country who can opt to enforce chat scanning.. so to me that means the former, not the latter.
In fact, isn't the latter already a thing? ...I believe companies can already scan chats voluntarily, as long as they include this in their terms, and many do. A clear example is AI chats.