Managing investments with 50% of salary will be the most difficult task and can be risky. Whether your income is low or high, your expenses will be determined based on your income. The demand of a person earning $200 a month and the demand of a person earning $2000 will not be the same. As your income increases, so will your expenses. You may think that if a person earning $200 can meet demand with $150 then I will earn $2000 and meet demand with $150 then you are wrong. If your income is $2000, your demand will also increase to $1500. So I think investing with 50% of income is one of the most difficult decisions for both low income and high income individuals. Many times such a decision may force you to sell your investment at a loss.
I can't full agree with you on this, because if a person has a monthly income of $2000 then investing 50% may not be that difficult for them, if they are conscious of their spending and stop all waste, they can easily invest 50%. can
Similarly, if a person's monthly income is $500, then he can invest 50 percent. (In today's age every family has wasteful expenses, they spend money on things they don't need) If a family can completely stop those wasteful expenses and be aware of their monthly income and expenses, a person earning $500 a month can easily spend 50% of their income. That is, $250 can support his family. And the remaining 50% can be used for investment.
A $2000 earner and a $300 earner don't have the same monthly expenses, but they both have wasted spending, and in that wasted spending they lose a lot of money that could have kept their family going for another week. In today's era, the minimum income of an employee is $300, and 50% of his income is $150. In our country, a family can easily survive for a month with $150. However, he must be sustainable to invest 50%, through proper budgeting and conscious spending.
I believe a person earning $300 can easily save 50% of his income i.e. $150 with a little effort, and if he starts investing regularly in DCA at that rate then in next 8 to 10 years i.e. next 2 to 3 cycle of Bitcoin After he will definitely be able to go to a much bigger stage.
I understand your point infact investing 50% of one's income and keeping the remaining 50% for their family expenses is not a bad idea but their are certain things you'll need to consider before making such decision. For instance when their's inflation, someone who normally do 50/50 on investment and expenses would need to adjust cause at that point their family's demand would increase based on the cost of living that is prices of goods and food items during that period so adjusting from 50/50 to 60/40 or 70/30 if need be is not a bad idea, that is 60% for family expenses and 30% for investment, the person can still readjust when things get normal and so far they continue with the DCA Method, I don't think adjusting their investment budget won't really be an issue to their investment plan since they're still doing it periodically overtime and can still readjust back when the economy gets back to normal. Another thing to consider is the size of the family, if the size of the family won't affect the person's income when the split 50/50 then it's fine but when the family size start getting larger to a point that the income can contain splitting 50/50 then they person would also need to consider adjusting as well.