What is Unified inbox?
One queue that collects replies from every connected mailbox (and LinkedIn account) so nobody has to log into senders one by one.
Cold email at volume means many sending mailboxes, and replies scatter across all of them. A unified inbox polls every mailbox, threads each reply with the messages that prompted it, and lets you answer from the mailbox the prospect wrote to — keeping the conversation on the warmed sender and in the same thread. The better ones classify replies by intent so the queue is sorted by what matters.