Apply lazy-loading for all images that are not visible on the first load, for example:

• everything "below the fold" (not visible before scrolling)
• carousels after the first slide
   
  Reference: https://www.andreaverlicchi.eu/lazy-load-responsive-images-in-2019-srcset-sizes-more/

Note: in some cases (e.g.: the Carousel Header) we get the src attribute for an image and use it as a url() background, investigate applying lazy-loading in that scenario.