If you are a holder since 2015, I can assume then that the big jump of 2017 happened for you without enough skill to sell at least a fraction of your bitcoins, perhaps believing that the price would grow well beyond the 20K barrier.
Therefore, I think I should not be too enthusiastic about your predictions, unless you prove that you were able to predict this great fall observed throughout 2019.
Yes you are correct, like most people at the time i knew things were getting out of hand and growing too quick in late 2017; as they say once your taxi driver asks you about bitcoin and where they can get some you know its time to get out! But accurately predicting the top is completely impossible, i thought at 12K it was getting fairly near and then of course we went all the way to 20K. At this point when it dropped a bit i thought maybe it would correct back to 14K and then climb back up again. Hindsight is always great but anyone who says they could have called the top and the subsequent year long fall from grace is obviously deluded.
Would be nice to think i could have sold 50 coins at this point and then bought them back in December for a cool 850K profit but you should never dwell on what could have been its what is going to happen that's important.
My strategy has always been a long term holder as i ultimately believe in the concept, of course its probably just as likely to correct to 3K as it is to break 6K within a few weeks but that's the fun of crypto investing.
If i wanted as easy ride i would hold coca-cola shares or invest in government bonds.