How to conditionally select a property using JMESPath

e.g., from the data below I need to select names based on the preference:

[
  {
    "first_name": "Waseem",
    "last_name": "Khan",
    "preferred": "first"
  },
  {
    "first_name": "Jawad",
    "last_name": "Hussain",
    "preferred": "last"
  }
]

should return to:

[
  {
    "name": "Waseem"
  },
  {
    "name": "Hussain"
  }
]