I the archives the default view is "topics". I never look at messages by topic and have been missing messages because only the first message is shown in this view. I just didn't notice what was happening because I don't belong to a list that emphasizes subjects.
But I have to choose messages everytime I look at one of the groups.io websites.
Perhaps if the program can't set a preferred view for each user, it could be an option for to set for each list.