I found this because I was trying to set up a feed for Instagram as they suggest here (although the domain is "instagr.am" instead of "instagram.com" ...
http://blog.instagram.com/post/8755963247/introducing-hashtags-on-instagram
- as well as in this article about the Instagram contest ...
https://help.instagram.com/464700830247492/
The inability to work will not be due to the user "tags", because this person is active long before the date of disappearance. It would seem that it was outdated, because this is not the type of thing that could be a “buggy” and (if it was), it would have been deleted with an error long ago.
What is strange is that if they refused this, one would think that they would announce their intention, as Twitter did. Given that these are the only results (dated October 1, 2014) that appear when you search [instagram rss feed not working] on Google, it seems that it was not used very much .; -)
However, Instagram could at least update its web pages if the goal was to simply shift it all (Twitter did “this is the end of RSS” when they announced “more RSS”). For social business, they probably love closed walls, don't they.
The suggestions above work well. I’ll look at the API or possibly use feed43.com, which is directly removed from any page that changes quickly and has predictable formatting (it works well, although the feed will break every time or twice a year when the site changes its formatting - easy to fix).
Hope this helps another person wonder.
PS I spoke too fast. I dug deeper after posting. There are several other pages below in SERPs that RSS is not working. It seems to have started on September 29th. There were no official answers that I could find.