Edits don't seem to carry over with 100% fidelity when sharing a photo to Instagram

instagram only uses the sRGB color space and will convert from anything wider (your phone can display much more saturated colors than sRGB) will be clipped to sRGB. So when you go to an app like instagram, your saturation will decrease if you have very saturated colors in your image. Instagram also only uses 1080 pixels on the long side for most images, so the resolution will go down drastically. This can also cause a change in appearance. Again this is just a consequence of the platform and you can't really do much about this except for optimizing your export settings for it (export to the exact dimensions instagram uses and enable output sharpening for the display).