SIO491: What Do We Actually Know About Tyler Robinson? Why Did He Kill Charlie Kirk?

The public has gone through several phases of evolution on what the shooter's motive was. At first, it was assumed he was a leftwing terrorist. Then it seemed clear he was on the right. Or maybe nihilist. Then, the charging documents were released. These contained some selected texts with Robinson's transgender roommate who he seems to have been in a romantic relationship with. They are... weird. But what is going on here? What can we actually reasonably conclude at this time?