Mailing list sucks.
I agree with this. I almost never reply to the mail list because I really have no idea how to do it without top-posting (I subscribed to daily digests). Simply, mail lists have only a single advantage -- everyone has an email. No code highlighting, quotes in digest are a bunch of '>' symbols and no threading.
We absolutely should move to a forum on boost.org for all things, import as much as we can from the mailing list (as far back as possible) into the forum, and then cease the use of the mailing list forever. Anyone who emails the list should get an automated reply that says "Please register for the wonderful forums at boost.org" etc
With something like Discourse you can still use the old and good email to reply to posts (like on GitHub) and even to create threads ( https://meta.discourse.org/t/can-i-start-a-new-topic-by-sending-an-email-mes... ).