Heavy images are the silent killers of site speed. To fix this, start by...

https://oscar-wiki.win/index.php/How_to_Test_If_Your_Images_Are_Slowing_Down_Your_Site

Heavy images are the silent killers of site speed. To fix this, start by renaming files with descriptive keywords instead of generic numbers. Add helpful alt text so search engines and screen readers actually know what they’re looking at