Web page is loading media twice on Mac OS safari?

Question:
Hey,
anyone tested their site speed and found it overwhelmingly slow?
I have an autoplaying video that I have gotten from the Wix media gallery but to my surprise the video size was 12Mb which was way too much for what I needed so I downloaded the full video and compressed it to 6Mb (Half the size!) and then uploaded it back to my homepage.

Problem?

  1. When publishing the site and loading it again from any browser type after removing cache and testing the loading time the site is still the same slow speed as before, and I can confirm that checking the site Network packages shows me that my compressed file was not changed a bit and is still 12Mb in size.
    is there an upscaling technique that happens in the background that I am not aware of?

  2. I have noticed that in Mac OS safari that the site is even slower compared to other browsers like chrome and Firefox and checked the packages in the Network monitor in the browser and saw almost double data size received by the client.
    when checking I saw that for some unknown reason the Safari browser seems to be loading the Video media twice!?
    Here’s a photo:

  3. This is not a major problem but if there are any tips to make the web page content load faster other than reducing Img sizes and file sizes I’d love to hear some experienced people seems like the web pages load an insane amount of js files that I’m afraid could be adding some extra unnecessary load to the website.

Product:
Wix Editor, Wix Studio Editor Safari Browser.

Thanks in advance,
Ben