We were unable to display all of the projects from dev.azure.com on the portal.azure.com homepage. This behaviour is intended, and you may provide feedback in the following thread: DevOps Project is not shown on the "Azure DevOps Project" blade.
If it is important to you, you can submit your request for this feature on the suggest a feature site:
![enter image description here](https://i.stack.imgur.com/OmR28.png)
Hope this helps.