It was added with the update, and it looks to be more of a reference to what nozzle you are using , rather than a preset to use .2 size nozzle ( i didnt see anything in studio yesterday that would point to a preset for that size ) + no .6/8 ?
I selected the add custom printer at the bottom ( bambu studio*, prepare, printer ) which allows you to create a nozzle for an existing printer as per the wiki (above) , so it appears there are multipule ways to add a nozzle size ( im still learning so its all good ) plus i will add the wiki comes with numerous templates for filaments and other settings , its an interesting read.
*context (edit)
this is slicer software.
The topic, is the lack of choice in the printer menu on this one, single, model from bambu