Perhaps i missed something. But Export for web should reduce the file size as I understand. As you could see at the picture it just doing the opposite. It scale up the pictures ( example from 4160x6240 to 12480x18720 ) and you see on the attached picture the file size is growing from 11MB to 42MB .... ( I don't use this feature, so I leave it here )
Is something not working like it should? Let us know.
I can see you're using the 3x preset – this exports an image at 3 times the original size. Usually, this is used when you're working on visuals for high-res displays, both for the web and, for example, when creating Xcode assets. If you'd simply like to compress an image, you can use the 1x size (making sure to adjust the compression options, too).
Ok, thanks for the reply.