Considering there were some plain old John and Jane Q. Public users who a) complained that the Instagram ecosystem was now polluted with Android users, and b) did switch to other photo sharing apps, it wouldn't be out of the question. Heck, even Twitter co-founder Jack Dorsey dumped Instagram, but not because of Android. Instead, he dropped the app after Facebook acquired Instagram; it's well known that Twitter looked into buying Instagram itself.
According to 9to5Mac, after Schiller deleted his Instagram account, a reader reached out to him by out Twitter for an explanation. Schiller told the reader that he quit Instagram because it “jumped the shark” when it expanded to the Android platform.
However, reader Clayton Braasch got in touch with Schiller via email, and got a response which is definitely more diplomatic.
"Instagram is a great app and community. That hasn’t changed.
"But one of the things I really liked about Instagram was that it was a small community of early adopters sharing their photographs. Now that it has grow(n) much larger the signal to noise ratio is different. That isn’t necessarily good or bad, it’s just not what I originally had fun with."
It's true that a larger community means more noise, stuff from folks that you may not be interested in. However, since you have to follow people, it's unclear why that would be a really big issue for Schiller, or any other Instagram end user.