Is it possible to download the new 2022.2 version of the add-in without using the Microsoft Store?
I've found this page but, for the time being at least, it's only offering the 2022.1 version:
Download ArcGIS for Office (esri.com)
Will the 2022.2 version also require a (new) set of portal resources be installed within ArcGIS Enterprise?
ArcGIS for Excel (2022.2) is offered as Software as a Service, with no more local managed installers required to install the s/w. ArcGIS for Excel is only available to download from the Microsoft store. Please check this doc link on how to 'Get the ArcGIS'. For What's changed and What's new in the 'ArcGIS for Excel', Please check out this blog post.
In the 'ArcGIS for Excel,' you can connect to ArcGIS Enterprise without installing any portal resources files on ArcGIS Enterprise.
The add-in now requires me to change my privacy settings, and even then won't run due to an organisational policy restriction; no such problems with the previous version.