I updated all 3 applications to 2.1.0.1736 today, using the MSIX versions on Windows 10.
Publisher claimed the Store content was not installed, so I told it to install everything, and watched everything downloading/installing. When it was finished, Photo and Designer still claimed none of the Store content was present.
At one point while Publisher was doing its work, I could see in Photo and Designer that Store content was being downloaded, but once Publisher was finished, both were back to saying nothing was installed.
Stopping and restarting Photo and Designer did not help.
After I stopped and restarted Publisher, it showed nothing installed, too.
Note: There have been a few times when running various of the 2.0.4 applications on Win 11 that they have surprised me when I tried to stop them by saying that they were delaying to finish content installation. And I think I've seen that with earlier 2.1 beta builds too. So I'm not sure what's going on. This is the first time I've caught it where I know the exact sequence of events.