So, does Groups.io allow a group to adjust its email delivery
settings
so that posts to the group from individual members will still always
show the sender as <[email protected]>, instead of the
personal
address of the sender?
?To be clear, the Sender field does always say (the Sender field is not normally displayed in an email user interface, but you can see it in the View Original, View Source, or View Full Headers function (whatever your interface calls it). And if your member's filter will allow him to use that field instead of the From field that would be the easiest fix.
I believe you mean the From field. An has been discussed, but I don't believe it has been implemented.