Access company branded templates from within Office apps

Rune Myrhaug thank you for sharing the information!

That's exactly what I would like to achieve (the ability to use templates with Office Online would be great too, but it's not our priority at the moment).

Looking at the date of this article:

https://mattipaukkonen.com/2019/12/03/sharing-office-document-templates-from-sharepoint/

it seems that the ability to store templates is available since early December 2019.

Another interesting side note: the OfficeTemplateLibrary value has been added to OrgAssetsType parameter in the sharepoint-ps/sharepoint-online official Microsoft Doc on February 2nd, but thanks to Ian Moran's blog post, not due to an internal push (see this commit on GitHub).

It's sad that there has not been any clear announcement or guidelines from Microsoft besides the few rows I posted in my opening message.

Also, in this comment (2018):

https://techcommunity.microsoft.com/t5/microsoft-sharepoint-blog/announcing-new-file-template-management-for-document-library/bc-p/284266/highlight/true#M2991

Chris McNulty said that Microsoft had announced a "new central CT/template management capabilities to be released in the next year". However, looking at more recent comments to the same blog post, people are complaining about the lack of information about the feature.

Let's hope Chris will see this and will be able to provide some clarification!