Updates to the Steam database as shown on steamdb.info don't mean anything unless there's content being added or changed. In this case no content was ever added or any details about the game even uploaded to the Steam database. Sometimes a change in the Steam database means everything gets an 'update' but the specific content in the database hasn't changed. See http://steamdb.info/faq/#changenumber for more information. The Steam database can be pretty confusing, sometimes the reasons for things changing isn't always clear.
To clarify, updates reported in the registry don't necessarily mean anything (obviously masked apps that have nondescript updates 10 times in a day are being actively worked on, for instance), but it's not overly difficult to separate the wheat from the chaff. Ever17 may be dead but it's clear that Owlboy still lives despite the complete lack of public info, for example.