The tab title and the tab itself are because how Qt has it by default. if you see any Qt opensource app like kdenlive scribus etc. they all have these duplicate title and grab area for tabs. the tab area is for arranging the tab and the title area is for grabbing the docker out of the docked group. In other applications these tabs are placed at the bottom of the docker while here we keep it at top thus making the duplicating titles more obvious.
If we want to remove title underneath the tab
marked with red here. Then you would have to make the tab also the grab area for the docker.
@halla had already linked a different implementation in the earlier Ui design thread perhaps that will be interesting to look at.