You have a 91MB page load on just the Ocean Portfolio in the designer. Full res images. On publish the images are being responsively optimized. Try to do that on your local machine with Photoshop. See how long it takes. I am actually surprised the designer even is able to complete the publish task. Kudos to Webflow for that.
So on the published page you are still creating over 326 requests and a 20.73 MB payload for the browser.
I am a photographer as well. I understand what you are trying to do. I would not attempt what you are doing on Webflow for performance reasons and the nightmare of prepossessing images after making design changes. I want people to see my work, not spinning beach balls. Most people bail quickly if the page load takes to long. A reason why lazy loading images on a large gallery is a must. You are loading 122 images on this page.
Inspecting the page source shows images with dimensions of 1920x1275 that are scaled down even on my 4K monitors. So to when the page is loading on a smaller viewport the client is buried with an unnecessary load of that 1920px image.
Personally I ruled out Webflow as a delivery tool for photo galleries where the images are served via the CMS and the CDN. I had a client that really wanted it to work for them and researched Cloudinary and ImgIx exhaustively. Can you pull this off using them with Webflow to handle the images src references, with support for lazy loading , responsive image generation and even DPI versions of images, and more. With the additional benefit of security, watermarking, on the fly generation as well.
Personally I would compare this to square pegs in round holes. At this point Webflow simply is not cut out for this use case. Might sound harsh, but I have worked on projects that involve millions of images. If you want personal help migrating this minefield, PM me. I will try to throw you a lifeline.