I have to say that it is true!
Single Mailbox Recovery (SMBR) runs on the Exchange server on which Microsoft Outlook is running, and it uses native Microsoft Messaging Application Program Interface (MAPI) protocol to communicate with the Microsoft Exchange Server that is running on a separate machine. SMBR also requires for the SnapCenter Plug-ins package for Windows (SCW+SCE) to be installed on the Exchange server. The SMBR architecture requires that you have SMBR installed on the Exchange server.
SMBR passes a query to identify the host name for Exchange, hence the backup snapshots will only load on the active server