Calling that a "declarative language" is just aggrandizing the mundane. The relevance is zero.

For that matter VB6 uses just as much of a "declarative language" in specifying user interfaces:

Code:
Begin VB.Form Form2 
   BorderStyle     =   1  'Fixed Single
   ClientHeight    =   4020
   ClientLeft      =   45
   ClientTop       =   375
   ClientWidth     =   5580
   BeginProperty Font 
      Name            =   "Tahoma"
      Size            =   9
      Charset         =   0
      Weight          =   400
      Underline       =   0   'False
      Italic          =   0   'False
      Strikethrough   =   0   'False
   EndProperty
   Icon            =   "Form2.frx":0000
   LinkTopic       =   "Form2"
   MaxButton       =   0   'False
   MinButton       =   0   'False
   ScaleHeight     =   4020
   ScaleWidth      =   5580
   ShowInTaskbar   =   0   'False
   StartUpPosition =   3  'Windows Default
   Visible         =   0   'False
   Begin VB.CommandButton cmdCancel 
      Cancel          =   -1  'True
      Caption         =   "Cancel"
      Height          =   495
      Left            =   4200
      TabIndex        =   17
      Top             =   3420
      Width           =   1215
   End
   Begin VB.TextBox txtField 
      Height          =   375
      Index           =   2
      Left            =   960
      TabIndex        =   5
      Top             =   1080
      Width           =   2055
   End
.
.
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