This is a functionality that is found in a lot of other Kanban boards out there and was found very helpful by our teams. They constantly request that if they are able to filter the Kanban board to see only the tasks that they are assigned.
In Agile, there is no limit on the number of Kanban team members. Sometimes when the teams are large or if there is a lot of work that is ongoing, it is helpful to be able to filter the work on the board by person. If I was to click on the little image of myself above the Kanban board, it would be great if this button would only show the items that are assigned to me.
The board can be a lot of work to maintain without this functionality. We are spending a lot of time looking for projects on the board at this time.