Second, the fact that we did not meet or hear from Dax. Timespan aside (and the novels established that symbiont lives can be *extremely* long) I'm glad for this. Had Dax been present instead of Tal, its previous hosts appearing would not have allowed us to focus on what the final scene was for. The hype would have been all about seeing Jadzia and Ezri again, and pulled too much attention from the goal of this being Adira and Gray's moment to reconnect. Likewise, a Dax as another cameo character wouldn't have really served the story at this point.
This is a really good point. If they had used Dax, I would've been happy with CGI versions of the hosts we knew as of DS9.
Basically non-interactive like most of what we saw. Similar to this 12 Doctors scene:
