2.1-2 Does it matter whether other people consider a work to be “offensive” or “mediocre”?

No, aesthetic or moral aspects must be excluded when it comes to the question of copyright protection of a work. It is irrelevant why the work was created. However, the rights of others can be infringed by the work, in particular the personality right, or the work can be considered a crime, e.g. defamation.