Nesting secondary loops

Hi folks!

In my plugin I’m running a secondary loop as follows:

function my_code() {
  // ...
  $query = new WP_Query( array(
    'p' => $post_id,
    'post_type' => array( 'post' )
  ) );
  if ( $query->have_posts() ) $query->the_post();
  echo "- My post: " . get_the_ID() . "\n"; // Expected $post_id.
  $content = get_the_content();
  echo "- My post: " . get_the_ID() . "\n"; // Expected $post_id, but I get something else.
  // ...
  wp_reset_postdata();
}//end my_code()

The problem arises when I retrieve the content of my post: there’s a third-party plugin that runs a secondary query when I get the content of my post and this messes my own query.

Here you have a Minimal Working Example:

function nelio_test_queries() {

  $query = new WP_Query( array(
    'p' => 1, // /!\ Set an ID here.
    'post_type' => array( 'post' )
  ) );
  if ( $query->have_posts() ) $query->the_post();
  echo "- My post: " . get_the_ID() . "\n"; // Expected 1

  second_plugin_does_some_stuff_via_hooks();

  echo "- My post after the second plugin did some stuff: " . get_the_ID() . "\n"; // Expected 1
  die();

}//end nelio_test_queries()
add_action( 'wp_ajax_nelio_test_queries', 'nelio_test_queries' );

function second_plugin_does_some_stuff_via_hooks() {

  $query = new WP_Query( array(
    'p' => 2, // /!\ Set an ID here.
    'post_type' => array( 'post' )
  ) );

  if ( $query->have_posts() ) $query->the_post();
  echo "- Related Post: " . get_the_ID() . "\n"; // Expected 2
  wp_reset_postdata();

}//end second_plugin_does_some_stuff_via_hooks()

Call the example via AJAX:

jQuery.ajax({
  url:ajaxurl,
  data:{action:'nelio_test_queries'},
  success: x => console.log(x)
})

and the expected result is:

- My post: 1
- Related Post: 2
- My post after the second plugin did some stuff: 1

but what you’ll get is:

- My post: 1
- Related Post: 2
- My post after the second plugin did some stuff: 2

How do I fix this? Keep in mind that I don’t know if the third-party plugin is or is not installed… Moreover, it’s not about this specific third-party plugin; any other plugin or theme that hooks into WordPress and runs whilst my secondary query is still active can mess my own code ??

Any help would be appreciated!

P.S. I know I can use $query->reset_postdata(), but do I really need to run it every time I call a function such as get_the_content or get_the_title, just to make sure that no other plugins changed the secondary query I’m running?