Spotless has certain drawbacks:
1) It is not able to verify license headers for non-Java files. For instance, it skips `package-info.java`, it skips `*.kts` and so on
2) Its error messages are too verbose. Sometimes it prints the full stacktrace when just one line was enough: "file X line Y column Z has error: ..."
3) It uses unsafe Gradle APIs, so it will be incompatible with Gradle 7.0
I suggest to replace it with https://github.com/autostyle/autostyle
Note: I tried to contact Spotless authors, and their way to manage code makes it very hard to co-operate (