Why do people create incredibly complex, fake identities online?

I've seen this happen a few times over the years and I always wonder what motivates the person doing it.

Here's some old internet history on the subject:

Several years ago there was a twitter account who went by @Sciencing_Bi who pretended to be a Native American anthropologist at Arizona State University and had been sexually harassed by a faculty member from Harvard.

Sometime in 2020, the owner of the @Sciencing_Bi account decided to kill off the "woman" who was writing the account. Of course, the "cause of death" was Covid. But when people who were her friends showed up to mourn this person, it was eventually revealed that she was fake all along.

Read more here

What makes people do this? What do they get out of deceiving people online? Is it just a larp? What is the difference between obscuring your identity for privacy and straight up deception?

Would love to know your thoughts!

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