Microsoft has a long history of dynamically changing product names as their portfolio evolves. In this instance the name changes affect Microsoft 365 and Azure Security workloads.
The idea is to group together security workloads and functions under the Microsoft Defender and Azure Defender umbrella.
Changes for Microsoft 365 workloads:

The first change I want to cover is Microsoft Threat Protection is now Microsoft 365 Defender.
Azure Advanced Threat Protection has changed its name to Microsoft Defender for Identity.
Microsoft Defender Advanced Threat Protection is now Microsoft Defender for Endpoint.
Office 365 Advanced Threat Protection is now Microsoft Defender for Office 365.
Changes for Azure workloads:

Azure Security Centre Standard Edition, is now called Azure Defender for Servers. .
Azure Security Centre for IoT is now called Azure Defender for IoT.
Advanced Threat Protection for SQL is now called Azure Defender for SQL.
Other recent name changes include:
Office 365 -> Microsoft 365
Office Pro Plus -> Microsoft 365 Apps
Azure Information Protection -> Microsoft Information Protection