They might. But Steinberg doesn’t make a lot of maps or playback templates on their own. Most of the maps are made by end-users and are of varying quality and standards because they are done by different people. There is currently no central repository for Dorico to find playback templates or maps online via some kind of service, instead it is up to the user to check a few different sources.
One such source is the Playback Template page on the Dorico Blog: Playback Template – Dorico
That has links to download playback templates made officially by Steinberg and also some end-users.
That page is not complete though. There are also numerous maps available in this thread, some of which are on the Playback Template page and some of which are not:
And @benwiggy posted a template for Berlin Free Orchestra in this thread, which apparently was forgotten to link to in the master Expression Maps thread:
Although the template in that first post excludes the unpitched percussion maps, in the last post a user created percussion maps and uploaded them in a separate zip file.