I believe they know from onboarding processes what type of user is passive and the ones that will be CRAZY active. They do not want these passive users - no benefit. Try this:
1. A old android/iPhone
2. Dump about 50 contacts (you may google for VCF)
3. Open all sorts of yellow press - from dailymail to tmz etc. Make you browsing history rubbish. And give all permissions from location to notifications etc to every website.
4. Click on some non-prominent personality's IG/fb name in some website. When it prompts you to install IG from app store proceed further. Do on boarding with defaults (i.e) allowing all permissions.
5. Instead of following popular people only in IG, search and add random people.
6. Everynow and then just make some photos of some tree or rubbish and upload.
7. Keep this phone as a junk phone.