Block Blueprint - Label {{count}}

What am I missing here to show the number of images in a Block’s label? I am currently using

label: “{{photos.count}}” Image(s)

name: Image Gallery
icon: grid
label: "{{photos.count}}" Image(s)

tabs:
  content:
    fields:
      photos:
        label: Gallery Images
        type: files
        layout: cards
        size: small
        empty: No images added yet
        multiple: true
      

That’s not possible, the label can only take a field name from your block’s fields as input, this is not query language but a string template, even if it looks the same.