Hello,
The latest releases of the e2fsprogs base libraries are now checked for backward binary compatibility here: https://abi-laboratory.pro/tracker/timeline/e2fsprogs/
The tracker is based on the open-source tools:
https://github.com/lvc/abi-tracker
https://github.com/lvc/abi-compliance-checker
Hope the report will be helpful for users and maintainers of the library.
Thank you.