Apart from most of your comment being irrelevant for immediate mode UIs, the rest is also at best misleading, since in modern 3D-APIs draw commands are also iss

Apart from most of your comment being irrelevant for immediate mode UIs, the rest is also at best misleading, since in modern 3D-APIs draw commands are also issued from scratch each frame (if only to kick off GPU shader code). The very early D3D versions actually had an optional 'retained mode API' in the mid-90's, but that quickly went the way of the Dodo.