This is what worked for me, as this has happened on two site servers after two different upgrades now (2103 and 2111).
Confirm this line exists under BgbSetup.log: "Failed to configure BGB server application with the error 0x80070430"
Then I used this article to get the main information on how to get the BGB server installing properly, but found it needed more information around security of the files that need modifying: https://www.prajwaldesai.com/fatal-msi-error-bgbisapi-msi-could-not-be-installed/
Take a backup copy of these two files under C:\Windows\Microsoft.NET\Framework64\v4.0.30319:
InstallUtil.exe.config
regsvcs.exe.config
For both files:
Change Owner to SYSTEM (was TrustedInstaller)
Change Security to Administrators Full Control (if can't save, change Security to SYSTEM Full Control too)
Add section
<runtime>
<loadFromRemoteSources enabled="true"/>
</runtime>
Reboot
Article says to restart Windows Services (Distributed Transaction Coordinator and SMS_SITE_COMPONENT_MANAGER) but it's quicker sometimes just to reboot the server.
Not 100% sure if the regsvcs.exe.config file actually needed changing but did so anyway.