Custom filter to remove default image sizes (WordPress and WooCommerce) from your theme.

wp-remove-default-image-sizes.php

<?php
/*
 * Custom filter to remove default image sizes from WordPress.
 */
 
/* Add the following code in the theme's functions.php and disable any unset function as required */
function remove_default_image_sizes( $sizes ) {
  
  /* Default WordPress */
  unset( $sizes[ 'thumbnail' ]);       // Remove Thumbnail (150 x 150 hard cropped)
  unset( $sizes[ 'medium' ]);          // Remove Medium resolution (300 x 300 max height 300px)
  unset( $sizes[ 'medium_large' ]);    // Remove Medium Large (added in WP 4.4) resolution (768 x 0 infinite height)
  unset( $sizes[ 'large' ]);           // Remove Large resolution (1024 x 1024 max height 1024px)
  
  /* With WooCommerce */
  unset( $sizes[ 'shop_thumbnail' ]);  // Remove Shop thumbnail (180 x 180 hard cropped)
  unset( $sizes[ 'shop_catalog' ]);    // Remove Shop catalog (300 x 300 hard cropped)
  unset( $sizes[ 'shop_single' ]);     // Shop single (600 x 600 hard cropped)
  
  return $sizes;
}

add_filter( 'intermediate_image_sizes_advanced', 'remove_default_image_sizes' );
?>

@dangelion the only way I can see to prevent the "-sclaed" images from being created is to use the filter "big_image_size_threshold" and return a large value (px) for threshold. The default is "2560" pixels so setting it to something like "10000" would probably prevent the image from being created in most scenarios.

I also noticed there is another version of the image it sometimes creates with the suffix "-rotated", If you want to prevent these then use the filter 'wp_image_maybe_exif_rotate' and return false;