Just reading through this thread now it seems like some are making posting photos on Instagram a lot more difficult than it really is.
What I do...
I have folders on my mac where I save all my instagram shots. In iTunes I just set up those folders to sync to my phone and voila, they're there. I have a preset for instagram on LR to set max width in landscape shots to 1080px. For portrait orientation I set it the crop to 5x7 and again a width of 1080px. These setting makes all the shots fit perfectly. There are many very good photographers on IG, way better than me. So to think IG is just a platform for kids and snap shot takers is gross misrepresentation.
One way I have noticed that IG is effecting photography is the prevalence of portrait orientation photographs for landscapes. Many photographers are filling the frame vertically in order to have a larger shot shown on IG when traditionally those shots may have been shot in landscape orientation in the past. I will sometimes to the same for some cityscapes and street photography. I take on shot landscape and another portrait so that I can use each shot on what ever media I would like, (IG, web, print).