Global tag filter
Add a list of global tags that will always be included in the search, without the need to select them first. Notes including one of the global filter tags must never be shown in the notes list. Actually global filter tags must not be listed in the tag sidebar
either. Examples are trash, done or archive. Add a menu option "view/[X]
global tag filter" and a shortcut, e.g. F8 to turn the filter on/off easily.
Vasta
With the ability of notes to links (CN 2.0) one can also create a revision chain. To create a revision you would copy the note first (notes list, Ctrl+C, Ctrl+V, done). Tag the old one as "revision" and create a link to it in the copied note. Add "revision" to the global tag filter to hide revisions. Done. Really simple!
People didn't vote for the suggested implementation, but going up to the problem level can help bring in more voters.
I suggest you re-post the idea as "Ability to hide certain notes from view by default", which seems to be the most generic phrasing. It doesn't limit implementation to tags, special kind of tags, etc.
Customer support service by UserEcho