Everyone's account is separate and you can't access any person's data, etc. Only thing the manager can do is add/remove people from the group. If it's a child account being added, there can be restrictions, but otherwise everyone account is siloed, so no privacy issues to worry about. Your iCloud syncs to your iCloud account.
Only issue here is people that 2 terabytes are shared, so if someone in the group has a massive iCloud, then that could be problematic. But otherwise, this is probably cheapest way to gain access to apple news, music, TV+, etc for