Dividing discretionary income into 3 parts may not be a logical decision for everyone, because the same formula may not work for every investor. For example, there are two users who have $300 of discretionary income per month. The first of them may already have an emergency fund and a stable income. The other does not have an emergency fund and even his income is uncertain. In this case, the same 1/3, 1/3, 1/3 formula may not be realistic for both of them. Because the first person may be comfortable giving $200 in Bitcoin. But the second may be more concerned with putting a larger portion of his discretionary income into an emergency fund or reserve fund.
Each person needs to make a decision based on their situation and financial situation. A person who already has an emergency fund ready does not need to create a new emergency fund. These decisions should be taken by the first person you imagine according to his situation. A person whose income is unstable and does not have an emergency fund can divide his income into three levels. Each person should take each decision according to his own convenience, another person has done one thing does not mean that it will be right for him to take the same decision.
But yes, the more our fund, the better or more secure our holding will be. For example, we can divide our funds into how many levels, such as emergency fund, reserve fund, other fund, the more our number of funds, the more our security level will increase. But yes, it is not necessary to keep the same amount of money in each fund. We can use the emergency fund as our main, protective, layer and in the emergency fund we can keep an amount equal to 3 months of expenses or we can keep an amount equal to 3 months of income. We can keep some less money in the reserve fund and in other funds we can keep less money than the reserve fund.