These are all very welcome updates! We're currently in the middle of our journey towards a modern intranet and are testing out the Sharepoint Online functionality as a potential solution.
One thing that is hindering us is understanding the solution for the company homepage itself. Traditionally, this was a Sharepoint page which was joined to subsites and subsites and subsites, etc. Standard user behaviour on the company homepage is to search for content that may be relevant to them, such as people policies - and in that solution, they would be able to find them. However, in this newer model the search can only include results from the hub - and for a large HR department, they would likely need their own hub!
There doesn't seem to be any mention of the ability to adjust the scope of the modern search of a particular site to ALSO include results of other hubs/sites - and for that matter, people results. This is the main reason why we can't succeed with a Sharepoint intranet homepage - the fact that the search can only provide results within the controlled hub environment, and we don't want just 1 hub, nor do we want to replicate information just to support search.
I have read through the hub site planning document, but it avoids this question and assumes we have a separate intranet homepage solution somehow (https://docs.microsoft.com/en-us/sharepoint/planning-hub-sites).