.....One must have a plan where he must gather bitcoins before he start thinking to sell some of his holdings. How many Bitcoins are sufficent is a subjective question. So some people 100 Bitcoins are low while for many getting even 1 bitcoin is difficult.
I would suggest that how many BTC is not completely subjective - even though it is based on the setting of subjective goals... So if someone might tell you what his goals are, then you would likely be able to determine a quantity of BTC that would likely satisfy the goal.
So for example, if a guy tells you that in 10 years, he would like to be able to have a monthly income of $5k without having to do any work - beyond just keeping track of his various accounts... Then at that point you have some ideas of an approximate number of coins that the guy might need to work towards getting, and I would say that if he works towards getting close to 5 BTC for the middle of 2034, then that would likely be more than enough to meet his goals... and perhaps even 3-4 BTC might be enough... yet we cannot really know, so then he should work towards getting to 5 BTC within the next 10 years.. which may or may not be doable for all people, and if it is not doable.
Then if he changes his goal to the same kind of idea of cashflow, but with a back up target for 15 years, then I would suggest that by mid-2039, then he is likely ONLY going to need around 2.5 BTC by mid-2039 in order to reach that same objective of having a monthly income of right around $5k.. so then he has something that he believes that he might be able to reach, and if he speculates that inflation might eat away the targets, then surely maybe he could try to shoot for more BTC and to have some cushion in his goals, and so we can largely ONLY attempt to give some directional guidelines that might need to be adjusted with the passage of time...yet I would still suggest that aggressive accumulation of bitcoin should be part of the formula, and the details can be tweaked at various points along the way.
$5K is a huge amount for people living in country like mine i.e. Pakistan. Those who are in developed country like Europe or USA can have the luxury of having such high income per month but only few one here can have that much high income. Here average salary per month is 300$. So defiantly I can't go with this plan.
But having less income doesn't mean that people like me have no place in Bitcoin. The beauty of Bitcoin is that it's open for everyone. There are billions of people in the world who are not in banking system due to various reasons and Bitcoin allows all such people to have there bank account where they have complete control over there money.
Having said that I do agree that the person having $5k income per month can have 5 BTC in next 10 years. One thing I should add is that we dont know what Bitcoin price will be in coming months. What we have seen so far is that there are dip's after every ATH. In Nov 2021 we saw an ATH of around $67K but then few months later we saw Bitcoin going down below $20k. So if someone is accumulating Bitcoins by investing $5k monthly into Bitcoin then he might end up getting more then 5 Bitcoins after 10 years if Bitcoin keep taking big dips.