Yes, they are different colors.
So I am wondering ... How come when I uploaded the images with and without resize, it worked perfectly. But when you upload images with and without resize, this happens? I did some further tests:
1. Let me upload the original WITH RESIZE from here.
2. Select image, with RESIZE selected.
3. After upload with RESIZE option. Clearly the image is colored identical to the original. How you got that image of yours uploaded like that is a mystery, but it's not consistent with the X3 upload resizer.
4. Furthermore, let's compare my resized image with yours. I wonder how yours is 40% larger file size for the same resize dimensions 1600 px width. And the colors changed.
If I didn't know better, I would claim that your resized image is from an original with a different color profile than the uploaded un-resized original. The only other logical explanation, is that there is something very wrong with your browser in the upload process. Surely you would have to agree.
The only next step I can take, is ask a few other people from here to do the exact same process as me: Upload the original with "resize" option checked, and let's see if the resized version changes color. If the resized image is same color as original, surely you must admit there is a flaw on your side? Either you are uploading an original with a different color profile, of there is some serious problem in your browser.
I'm getting a bit tired making long responses and extensive tests to this post now. Clearly I have proved some points in my recent posts. The only next step if you still think the flaw is not on your side, would be to ask 2-3 users to upload the original image with resize-option checked (exactly as I did in this post). If the color of resized is identical with the original, surely you would have to agree the issue is on your side? In which case, I already gave you two logical reasons of how the issue might exist on your side.