Hi Leo, all:
You raise a fair question, Leo. However, I'm also inclined to think that we're going a bit in circles. As others have highlighted, we have tried other channels (like the Forum, but not exclusively that), and it's not really worked. There's also multiple social media channels, a Telegram channel, and other formal and informal communications methods.
I think there's merit in experimenting with new methods and channels (I think starting a RIPE DIscord channel, for instance, would be great if there's not one already). But email continues to be the most reliable form of communication I've come across throughout the Internet community, as it allows for asynchronous communication in an organised way (based on interests and sub-communities), anyone can easily join (via the signup form) as well as unsubscribe or switch to a digest, it's easily archivable, and it's easy to translate / accessible.
I agree with Joe that it's a sociological, not engineering issue – i.e., how we make people feel welcome, how we communicate with each other, and how we collectively agree to share information.
For these reasons, I think it would be a shame to eliminate the lists. Other methods can complement if necessary/desired, but shouldn't replace IMO.