We make constant decisions for our money and where to spend it. Personal finance skills help us make better decisions with our money.
Not learning about personal finance is irresponsible to yourself. You can continue to work hard to earn money, but you lose the benefit of using it in the optimal way.
The bottom line is that you are financially handcuffed and your choices in life will be limited. So irrespective of what you do and which stage of life you're at, you should know the basic finance skills.