Just checked and it indeed does link to a older version, it did work before.
Here is the link for 1.2.0
https://sdk.flightsimulator.com/msfs2024/files/installers/1.2.0/MSFS2024_SDK_Core_Installer_1.2.0.zip
https://sdk.flightsimulator.com/msfs2024/files/installers/1.2.0/MSFS2024_SDK_Documentation_Installer_1.2.0.zip
https://sdk.flightsimulator.com/msfs2024/files/installers/1.2.0/MSFS2024_SDK_Samples_Installer_1.2.0.zip