JSFiddle - React, Tailwind, and code Playground

JavaScript

var origArray = [   {
        "TypeName": "Single",
        "TypeID": "3121",
        "TypeCount": "2"
        },
    {
        "TypeName": "Double",
        "TypeID": "4056",
        "TypeCount": "2"
        },
    {
        "TypeName": "Family",
        "TypeID": "5654",
        "TypeCount": "4"
        }
];

var userArray = [   {
        "TypeID": "3121",
        "TypeCount": "2"
        },
    {
        "TypeID": "4056",
        "TypeCount": "3"
        },
    {
        "TypeID": "3121",
        "TypeCount": "3"
        }
];

function groupByTypeID(arr) {
    var groupBy = {};
    $.each(arr, function () { 
      var currentCount = groupBy[this.TypeID] || 0; 
      groupBy[this.TypeID] = currentCount + parseInt(this.TypeCount);
    });
    return groupBy;
}
    
var userArrayGroups = groupByTypeID(userArray);
var origArrayGroups = groupByTypeID(origArray);

var diff = {};
for (var prop in userArrayGroups) {
  diff[prop] = userArrayGroups[prop] - origArrayGroups[prop];
}
      
console.log(diff);