In this context, the "real insta" account is the curated one to build a personal brand; only highly-filtered/vetted content gets posted there. Due to all the time put into curating it, the account is intended to persist forever.
The posts to the "fake insta" has less of a filter, and the account will be dropped/rotated as soon as it gets too much baggage or some content goes negatively viral. Someone bothering the user on their "fake insta"? But the user can't/won't block them for social/cultural reasons? Just stop using that account and create a brand new one, and then only tell your close friends about the new one. Everyone else is still following the old "fake" one which you no longer use hence its fake-ness.
The posts to the "fake insta" has less of a filter, and the account will be dropped/rotated as soon as it gets too much baggage or some content goes negatively viral. Someone bothering the user on their "fake insta"? But the user can't/won't block them for social/cultural reasons? Just stop using that account and create a brand new one, and then only tell your close friends about the new one. Everyone else is still following the old "fake" one which you no longer use hence its fake-ness.