Not only its built in, but syntax is on another level, i.e. you don't need to learn special syntax if you know PowerShell. This thing alone makes pwsh worth it instead of using number of other tools.

    @{ Hello = 'world'; array = 1..10; object = @{ date = Get-Date } } | ConvertTo-Json
 
    {
      "array": [
        1,
        2,
        3,
        4,
        5,
        6,
        7,
        8,
        9,
        10
      ],
      "object": {
        "date": "2024-07-03T21:07:21.6562053+02:00"
      },
      "Hello": "world"
    }