IMHO you should look/ask for such a feature in a google group because big g may have a business case for such a feature: it would pull back in those users who try to escape.

and that should not be an immich feature but a google one.

as a self-hoster I prefer to have control on my data; a solution to feed my data to google through a third party (that may do whatever it wants while performing the transfer) is the exact opposite of what i’m trying to achieve and would have little to no value for me.