Our aim is surely to produce an accurate one world tree. The means to do this is by collaborating within the framework of a wiki. https://www.wikitree.com/wiki/Help:Collaboration
We don't own profiles because we were first on the scene or happened to create a duplicate,though because of the sensitivity of family history there is some leeway in the form of privacy controls for our nearer relatives.
Talking about 'offense' and what is favoured by the managing pm surely implies some idea of ownership;one tree of linked separate twigs, each run and linked in a manner consistent with the profile manager's own likes and dislikes.
In regard to style, and in particular adding things using inline citations on a profile that hasn't previously used them ( which appears to have been the original complaint) the guide says
"As you become more experienced and start to collaborate with other WikiTreers you will need to learn how to create references, i.e. footnotes, endnotes, or citations."
To me this makes sense. Changes or additions should be made with appropriate evidence. If after adding a fact or changing something you explicitly reference the new information, such a reference allows every reader, including the pm to see where the new information has come from. In many cases you can't do that by adding to a list of 'sources'. The ability to add inline sources is considered a necessary part of every profile and I would suggest that it is the preferred style for referencing.
" the <references /> tag should never be removed since references may be added later. Ideally, there should always be individual references but we appreciate that often there are not." https://www.wikitree.com/wiki/Help:Sources_Style_Guide
As for adding things without communicating, https://www.wikitree.com/wiki/Help:Communication_Before_Editing the section Be Bold shows that it isn't always a prerequisite to communicate before some changes .Even after communicating, It also doesn't ask us to wait indefinitely for a reply after leaving a comment (three days wish I had read that much earlier in my wiki-tree career, when I often waited months before going ahead and adding/changing long abandoned or neglected profiles)
The guide asks us to be aware of the amount of time, work that has gone into a profile before making changes. So if someone has spent ages on a narrative profile or a timeline then just jumping in and adding something without respecting the existing style might rightly be called impolite. On the other hand if there is no bio and just a couple of sources under the heading then I would think it was acceptable to add a biographic statement, complete with inline reference, or even a more detailed and again referenced resource note.