Keep in mind that you have to be vigilant every time you install updates. Microsoft can (and often does) release multiple versions of updates, and it appears the ignore flag is not preserved between versions.
The fact it still tries to peddle me SILVERLIGHT despite that getting "Hide Update"d every time it's ever been offered makes me think that (separate from W10-related strategic malice) there's also basic incompetence in the way Windows Update is designed/operated. I don't believe it's in MS's current interest to actively promote Silverlight and yet there it is again and again.
It's the Windows update system being a horrible mess instead of a proper package manager. Each time you hide it, what you get is apparently a new update with the same name. If you hide it enough times, you eventually hide every available update and it won't reappear (at least, until they issue a new one). Really annoying!