JSFiddle - React, Tailwind, and code Playground

JavaScript

var arr = [2, 500, 54, 99, 101];
var filtered = arr.filter(function(n){ return n < 100; });

function powerset(arr) {
    var ps = [[]];
    for (var i=0; i < arr.length; i++) {
        for (var j = 0, len = ps.length; j < len; j++) {
            ps.push(ps[j].concat(arr[i]));
        }
    }
    return ps;
}

var powerSet = powerset(filtered);

console.log('{' + powerSet.join('}{') + '}');