I think the answer to all of this is 'it depends'.

Is there already a ticket and are you working to update the app? Then update the documentation. No ticket necessary.

Are you redoing the whole set of docs to make the steps for new engineers to create their stack? Then please lets have a ticket to define the scope and audience.

Trust me that I do understand that there are many orgs that have arbitrary hurdles in place, like who can create / prioritize a ticket. My experience is, if engineers are empowered / encouraged to create and prioritize their own tickets, then its not a hurdle at all.