What's the issue with dependencies in Solus?
Why does gThumb need Brasero as a dependency?
And another thing, why doesn't its unnecessary gets removed when I remove the program?
Don't we have a command like "sudo apt autoremove" in Solus??
No such command for Solus with the current package manager eopkg. Once the new package manager is developed, this type of functionality will be considered. I say considered as it is an extremely delicate process and ensuring it works and doesn't break any libraries/applications/system functions is complicated.