Another data point working against you: no Bitcoin bear market has ever broken below the prior cycle's ATH. For that reason, sub-$20K is probably off the table.
The late '13 pump 'only' reached 4x the previous ATH of $260. And then it famously crashed well below it.
That's arbitrary. April and November 2013 were obviously two legs of the same bubble cycle. After that bubble popped, price remained comfortably above the 2011 high of $32.
Same idea after the 2017 bubble popped, with price remaining comfortably above the 2013 high of $1,163.
There is no guarantee this pattern will continue of course, but I wouldn't bet against it.
We're already just as vertical as the steepest parts of 2017.
To me, the angle looks like the April-May leg of the 2017 rally.