Remove some states from dropdown on billing step on magento 2.2

Vendor/Module/etc/frontend/di.xml

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <type name="MagentoDirectoryModelResourceModelRegionCollection">
           <plugin name="product_Limit_State_Filter_Plugin" type="VendorModulePluginStateFilter"/>
      </type>
</config>

Vendor/Module/Plugin/StateFilter.php

<?php
namespace VendorModulePlugin;

class StateFilter
{
  protected $disallowed = [
    'Guam',
    'Armed Forces Pacific',
    'Hawaii',
    'Alaska'
];
  protected $scopeConfig;
  protected $allowedUsStates;

  public function __construct(
    MagentoFrameworkAppConfigScopeConfigInterface $scopeConfig,
    MagentoCheckoutModelSession $session
  ) {
      $this->scopeConfig = $scopeConfig;
      $this->session = $session;
  }

  public function afterToOptionArray($subject, $options)
  {
      $result = array_filter($options, function ($option) {
          if (isset($option['label'])){
            // if($this->needHide()) { //remove this condition to hide them by default
              return !in_array($option['label'], $this->disallowed);
            // }
          }
          return true;
      });
      return $result;
  }

  public function needHide() {
    $blacklistSkus = array('sku1','sku2');
    $needToHide = false;
    $quote = $this->session->getQuote();
    if($quote->getAllItems()) {
      $items = $quote->getAllItems();
      foreach($items as $item) {
            if(in_array($item->getSku(),$blacklistSkus)) {
            $needToHide = true;         
        }
      }
    }
    return $needToHide;
  }
}

1. log in to admin
2. Go to stores > configuration > General > General > States options (Choose Required Country from drop down) from here
3. Save configuration
4. Go to PHPMYADMIN > choose table directory_country_region_name and directory_country_region
5. Delete the particular desired record from that table. (You have to do it from the database. Otherwise, you have to use all existing state options. Why because The states were added already right? To make any change, you need to access the database.)
6. Clear cache and re-index

I have removed them from the shipping step and I know this is not the perfect solution but we only ship to the US so it works fine for me.

create a module and create ModelCheckoutLayoutProcessorPlugin.php

<?php

namespace VendorModuleModelCheckout;
use MagentoFrameworkStdlibArrayManager;

class LayoutProcessorPlugin
{

    /**
     * @param MagentoCheckoutBlockCheckoutLayoutProcessor $subject
     * @param array $jsLayout
     * @return array
     */

    protected $arrayManager;

    /**
     * LayoutProcessor constructor.
     * @param ArrayManager $arrayManager
     */
    public function __construct(
        ArrayManager $arrayManager
    ) {
        $this->arrayManager = $arrayManager;
    }



    public function afterProcess(
        MagentoCheckoutBlockCheckoutLayoutProcessor $subject,
        array  $jsLayout
    ) {
    $jsLayout['components']['checkout']['children']['steps']['children']['shipping-step']['children']
                ['shippingAddress']['children']['shipping-address-fieldset']['children']['region_id'] =
                [
                'component' => 'Magento_Ui/js/form/element/select',
                'config' => [
                    'customScope' => 'shippingAddress',
                    'template' => 'ui/form/field',
                    'elementTmpl' => 'ui/form/element/select', 
                    'id' => 'region-state',
                ],
                'dataScope' => 'shippingAddress.region_id',
                'label' => 'State/Province',
                'provider' => 'checkoutProvider',
                'visible' => true,
                'validation' => ['required-entry' => true,],
                'sortOrder' => 80,
                'id' => 'region-state',
                'options' => [

                [
                    'value' => '',
                    'label' => 'Please select region state or province.',
                ],
                [
                    'value' => '12',
                    'label' => 'California',
                ],
                [
                    'value' => '13',
                    'label' => 'Colorado',
                ]
                ],
            ];  
    return $jsLayout;

    }
    }