Read the page I have linked you to again:
Basic - to read a user’s own profile info and media in early 2020
Essentially, that is interpreted as meaning Basic Display API is closing down in early 2020.
“Early” is subjective. It could be 1st January 2020 or 20th May 2020. Who knows! Instagram did a great job of pulling the rug from under many developers this year (myself included), without any warning.
The only API Facebook appear to be keeping alive is the Instagram Graph API.
But a quick browse of the documentation shows that this API is mostly dealing with Instagram integrations in phone apps. For example if you developed an Android or iOS camera app, there is potentially some stuff here that lets you add buttons that allow a person to share a picture or video into the main Instagram app.
If you look at the documentation from the perspective of someone wanting to build Instagram into a website, there’s practically nothing there. I have failed to find anything conclusive. And I believe that what you do decide to build with Instagram Graph API, has to be reviewed and approved by Facebook - similar to the Apple App Store approval process. No doubt a direct consequence of the Cambridge Analytica fallout.
Instagram cite security as the reason for shutting down all these APIs. Maybe for the phone and tablet apps. But it has never been feasible for an Instagram stack to gain access to your account and post data or steal sensitive stuff.
I think the truth of the matter is more to do with the fact that Facebook make their money through targeted advertising and mass data harvesting. So they want all our third-party stacks and other plugins banished, so everyone is encouraged to use the official apps instead.