I know there is a plugin to add other identities, but Instagram is really popular and I feel like it should be in the core along with:

(Current identities built in to core: AIM, Yahoo IM, ICQ, Google Talk, MSN, Skype, MySpace, Facebook, Twitter, LinkedIn, YouTube and Google Plus)

we can add it to our consideration list... 

one thing we will have to consider is what happens if a user has already added it via the add favorites plugin...  might cause issues...  thanks...

It i(instagram) is added in the Add-on Bundles...

However, I cannot see it can be untick inside the plug-ins.... I do request from support but being turned down and telling me to find the code. In this case, why we need to pay for the Plug-in for Add Identities ?

Cant comment further but with a disappointed heart ....