I am using the below code to create the validations in google sheet (contributed by Cooper), what this script does is it automatically check the applicable headers and create the dropdown with values and hide the columns which are not applicable.

I am trying to solve here is:

1. The script checks the applicable headers related to the Product Selection
2. It creates the dropdown with validation values
3. Instead of hiding the not applicable columns, It removes them from the sheet

I am a beginner to google script and tried using the deletecolumn function but unable to get it work.

Please help me out here.

function loadObjectsAndCreateProductDropDown() {
  const ss = SpreadsheetApp.getActive();
  const sh = ss.getSheetByName('Sheet0');
  const psh = ss.getSheetByName('Sheet1');
  const [ph, ...prds] = sh.getRange(1, 1, 10, 6).getValues().filter(r => r[0]);
  const [ch, ...chcs] = sh.getRange(11, 1, 10, 10).getValues().filter(r => r.join());
  let pidx = {};
  ph.forEach((h, i) => { pidx[h] = i });
  let prd = { pA: [] };
  prds.forEach(r => {
    if (!prd.hasOwnProperty(r[0])) {
      prd[r[0]] = { type: r[pidx['Type']], size: r[pidx['Size']], color: r[pidx['Color']], material: r[pidx['Material']], length: r[pidx['Length']] };
      prd.pA.push(r[0]);
    }
  });
  let cidx = {};
  let chc = {};
  ch.forEach((h, i) => { cidx[h] = i; chc[h] = [] });
  chcs.forEach(r => {
    r.forEach((c, i) => {
      if (c && c.length > 0) chc[ch[i]].push(c)
    })
  })
  const ps = PropertiesService.getScriptProperties();
  ps.setProperty('product_matrix', JSON.stringify(prd));
  ps.setProperty('product_choices', JSON.stringify(chc));
  Logger.log(ps.getProperty('product_matrix'));
  Logger.log(ps.getProperty('product_choices'));
  psh.getRange('A2').setDataValidation(SpreadsheetApp.newDataValidation().requireValueInList(prd.pA).build());
}

//I chose to use an installable dropdown.  I'm not sure if it's needed.  Its up to you.

function onMyEdit(e) {
  //e.source.toast('entry')
  const sh = e.range.getSheet();
  if (sh.getName() == 'Sheet1' && e.range.columnStart == 1 && e.range.rowStart == 2 && e.value) {
    //e.source.toast('flag1');
    sh.getRange('C2:G2').clearDataValidations();
    let ps = PropertiesService.getScriptProperties();
    let prodObj = JSON.parse(ps.getProperty('product_matrix'));//recovering objects from PropertiesService
    let choiObj = JSON.parse(ps.getProperty('product_choices'));
    let hA = sh.getRange(1, 1, 1, sh.getLastColumn()).getDisplayValues().flat();
    let col = {};
    hA.forEach((h, i) => { col[h.toLowerCase()] = i   1 });
    ["type", "size", "color", "material", "length"].forEach(c => {
      if (choiObj[prodObj[e.value][c]]) {
        sh.getRange(e.range.rowStart, col[c]).setDataValidation(SpreadsheetApp.newDataValidation().requireValueInList(choiObj[prodObj[e.value][c]]).build()).offset(-1,0).setFontColor('#000000');
        sh.showColumns(col[c])
      } else {
        sh.getRange(e.range.rowStart, col[c]).offset(-1,0).setFontColor('#ffffff');
        sh.hideColumns(col[c]);
      }
    })
  }
}

demo sheet

Data2 sheet tab:

UPDATED Sample Script

var sh = SpreadsheetApp.getActiveSpreadsheet();
var selection = sh.getSheetByName("Sheet1").getRange("A2").getValue();  //Get the selection on the dropdowm on cell A2
var data1 = sh.getSheetByName("Data1").getDataRange().getDisplayValues();
var data2 = sh.getSheetByName("Data2").getDataRange().getDisplayValues();

function addHeaders(sheet, values) { //Adds the headers from Column C and beyond
  var startCol = 3; //Column C
  var endCol = startCol    values.length;
  values.forEach(x => {
    if(startCol <= endCol){
      if(checkHeaderIfYesOrNo(x) == true)return;
      sheet.getRange(1,startCol).setValue(x);
      startCol  = 1;
    }
  });
 }

function onEdit(e) {
  if(e.range.getA1Notation() != "A2")return;//Make sure to run onEdit function ONLY when cell A2 is edited/selected
  var headers = [];
  var headerValues = [];
  var temp = [];
  var counter = 0;
  clean();
  data1 = fixDuplicates();
  //find selection name on data1
  for(var x = 0; x< data1.length; x  ){
    var name = data1[x][0];
    if(name == selection){
      ///get the headers & their values
      data1[x].forEach(res => {
        if(res != "" & res != selection){
          var index1 = data1[x].indexOf(res); 
          var index2 = data2[0].indexOf(res);
          headers.push([data1[0][index1]]);
          for(var y=0; y< data2.length; y  ){
            if(data2[y][index2] != "" && data2[y][index2] != res){
              temp.push("**" res "**" data2[y][index2]); //place raw header data to a temporary variable
            }
          }
          //Set the drop-down data of each headers
          temp.forEach(raw => { //clean the temp array
            if(raw.includes(res)){
              var regex = /\*\*([^*]*(?:\*(?!\*)[^*]*)*)\*\*/g;
              headerValues.push(raw.replace(regex, ""))
            }
          });
          //Logger.log("Data of the \"" res "\" header:\n" headerValues);
          //set data validation per header
          counter  = 1;
          if(res.toLowerCase().includes("no"))return; //skip creating data validation for "No" header
          if(res.toLowerCase().includes("yes")) return; //skip creating data validation for "Yes" header 
          sh.getSheetByName("Sheet1").getRange(2,2 counter).setDataValidation(SpreadsheetApp.newDataValidation().requireValueInList(headerValues).build());
          headerValues = [];
        }
      });
    }
  }
  addHeaders(sh.getSheetByName("Sheet1"), headers);
}

function clean(){ //Clean Sheet 1 on every edit
  sh.getSheetByName("Sheet1").getRange('C2:Z').clearDataValidations();
  sh.getSheetByName("Sheet1").getRange('C1:Z').clearContent();
}

function fixDuplicates(){
  var temp = [];
  var data1New = [];
  var count = 1;
  for(var x=0; x<data1.length; x  ){
    data1[x].forEach(findIt => {
      if(findIt.toLowerCase().includes("yes") || findIt.toLowerCase().includes("no")){
        temp.push(findIt count);
        count  = 1;
      }else{
        temp.push(findIt);
      }
    })
    data1New.push(temp);
    temp=[];
  }
  return data1New;
}

function checkHeaderIfYesOrNo(h){
  for(var x=0; x<data1.length; x  ){
    if(data1[x][0] == selection){
      if(data1[x][data1[0].indexOf(h.toString())].toLowerCase().includes("yes")){
        Logger.log(h  " contains Yes");
        return null;
      }else if(data1[x][data1[0].indexOf(h.toString())].toLowerCase().includes("no")){
        Logger.log(h " header will not be added as it has \"No\" value");
        return true;
      }else{
        Logger.log("Skip the " h  " header");
        return null;
      }
    }
  }
}

Sample Demonstration:

Sample Execution Log result for review: