Help my formatting toolbar is gone

In the XML Author mode, a number of the toolbars (especially anything to do with formatting) are simply not available. The intent is to have authors provide content and not have to worry about how it looks. The visual appearance is taken care of downstream in the structured FM application at the publishing stage.

Your toolbars are visible at the top, so I think you must mean panels/pods.

In my screen shot, I was showing the Design workspace. On your screen shot, you have the Authoring workspace selected. Click on Authoring (top right) and reset the workspace. And perhaps try out the other options. The job of a workspace is to control the visibility and position of the toolbars, pods and panels.

FrameMaker has changed a lot in 10 years. The panels/pods are distributed through the various menus. For example, to show the Paragraph Designer, you have to go to Format > Paragraph > Designer. To show the Conditional Text pod/panels, go to Special > Conditional Text select each of those. Basically, when you initiate an action, the appropriate pod/panel opens. You can dock them along the right side or bottom of your screen.

For example, this is a custom workspace that I use when teaching a new student. You can configure a workspace to look anyway you like. Note that this is the unstructured FrameMaker forum, so I'm showing unstructured FrameMaker.