If Dynamics 365 sits at the core of your business and HubSpot runs your marketing, the owner field has probably cost you more than it should. Per HubSpot's update, custom lookup properties in Dynamics 365, such as SDR owner and CSM owner, now sync in both directions with HubSpot, so you can update them from either platform. Keeping those aligned used to take extra fields and automation, and Joshua Oakes, reading why it matters, added "which I can attest to."
He also brought the client-project view: "I have not had to deal with Dynamics in five years or something on client projects, but that is easily the number one lookup slash enumeration that syncs between the systems that you have a headache for." His read: "it does seem like a long time coming."
My own take is about how each system is built. HubSpot grew up around the contact record and only got users as an object in the last year or two. Microsoft has always been built around the user record. Connect the two and "you run into stuff like this very quickly."
Two things to know before you plan around it. Joshua pointed out that it is live, not beta. And nothing changes on its own: properties aren't added or changed automatically, so you opt in and configure the sync yourself.
The next step