I lurk these forums quite frequently, and I've been hanging out since 2011. We all saw this dip coming. This is that dip where people say, "Fuck it, I'm done! It's not going to the moon EVER!" Pirate has stolen all of our money! etc..
The past is no reliable predictor of the future, but it's all we've got, so let's come up with some expected values based on intuition.
Let's say there's a 25% chance these bubbles will repeat themselves and over the next year we'll reach >$4000 level.
Let's say there's a 50% chance we'll stagnate at an average of $500 over the next year
Let's say there's a 25% chance we'll go to $0 over the next year.
0 * .25 + 0.5 * 500 + 0.25 * 4000 = $1250 expected value over the next year, for me at least.
So keep on selling and I'll keep on buying!
Looking at the charts of the past years seems that we are near the end of the stagnation period,
your calculations are made "for fun" but I think you centered the point, the train will leave the station after the weak hands will be out of the game.