Microsoft Brands Program (Business Profiles) is Microsoft's own inbox branding program.
The Microsoft Business Profiles team has notified all partners recently, that they are assessing other logo support options for the inbox, so they are pausing new onboardings for the Microsoft Business Profiles/Brands program.
The general hope is that it will be replaced with support for the BIMI standard, as they started to express interest in adopting the BIMI brand, but MS has not stated their official plans as of yet.
They will continue to honor the logos already in the system/being supported, but they are no longer accepting new customers for their Microsoft Business Profiles/Brands program. We hope to soon learn more about the logo support route they'll be taking (ideally, it'd be BIMI).
We will update this article when we will have more news from Microsoft as to whether they will want to implement BIMI as an inbox brand to their mailboxes.