[edited out].
That's true, someone who might have not known how these things works can easily be lured into investing in bitcoin and the person who lured the investor might not have properly explained to the investor how things works around bitcoin investment, especially in long term hold. Everything will just be unfolding as surprises to the investor. So it will be difficult for the investor to follow up the investment, because at the point of investment he was kept in the dark, and he might have just programmed himself that it will be a one time purchase.
This could rightly be the situation first guy found himself that made him not to follow up his investment, for that holding period of 9 years. Your explanation has given me a wider understanding to why some investors fails to follow up their investment after the first lump sum purchase. If the first guy was in a situation similar as you explained above, then I think he made the right decision by not following up the investment, because he would have ruined his life, because he would have find it difficult to sustain the investment and still take care of his other needs. Hence his decision to hold the first buy, and focus on his life is also not bad.
There may be some senses in which our hypothetical is not even realistic, since I would assert that many times someone who ONLY makes a one time investment into bitcoin and who is not interacting regularly, by buying more, then that person likely does not sufficiently understand bitcoin, so in that regard, there would have had been pretty high chances that the person who initially bought $5k worth of BTC would not have had been able to hang onto it for so long without selling some or all of it, so the more likely scenario from my own point of view is that the one time buyer would have had sold too much too soon.
Accordingly, some credit has to go to the 1st guy to hold bitcoin for 9 years without selling it, even though part of my point was to contrast the whimpy buyer with the more aggressive buyer, and surely there could be a lot of different variations, yet part of the objective of trying to show a comparison of two different types of persons should be to attempt to show how they might be substantially changed by merely changing one of the variables, and in this case I was trying to just show the difference between whimpy and aggressive and attempting to show that they might otherwise be very similar apart from the whimpy versus the aggressive approach to bitcoin investing.
And, surely there is no guaranteed that the aggressive would have had performed better, and each of us can choose between being whimpy or aggressive to the extent to which the balance makes sense to our own particular circumstances, and there may be times in which we change our approach based on some other goals (or projects or activities or purchases) that we might end up wanting to carry out in the midst of our bitcoin accumulation journey.