That may be so, although the author's own words doesn't clearly state that ("To clarify what I mean by decentralised: applications whose main purpose is fulfilled as part of a network, where that network is not reliant on any preordained nodes." - nothing about ownership there. Master<->Master db replication meets that definition, but is petty clearly not the type of thing you are referring to. Regardless in context you're probably right abouy which definition the author is using).

Nonetheless, that doesn't make it any less of a problem that the definitions are severely overloaded. The issue is not that the article is unclear in its definitions (even though it is imo), the issue is that its hard to have discussions about the topic and compare to other articles, because people talk past each other. Words having agreed meanings is important so we can connect ideas to a broader context and not just talk about individual articles in isolation.