I will agree with you that many times people have unrealized potentials in terms of both increasing their income and decreasing their expenses, yet there are also likely cases in which people are struggling within their own best efforts, and so they have difficulties (and perhaps even impossibilities) increasing their discretionary income.
Nothing is impossible when someone has a plan in their life and to achieve a much better financial source requires hard work by relying on existing opportunities and when we want to change our lives for the better, then every effort must be made to grow a much more stable income. The existing potential needs to be increased and at least be able to meet the needs of life and continue to try to set aside a little money to start investing. It may sound difficult for some people who do not have a steady source of income, but it does not mean it is impossible if they are willing to fight.
Sometimes you might have a plan for your life, but the problems we experience may stop us from achieving our goals. Hard effort does play a role in someone's life, but you must have what it takes to do it. Many individuals have been planning to invest in Bitcoin for years, but despite their efforts and preparation, they are still unable to become part of Bitcoin holders. Furthermore, you have said it all "That effort can grow much better with a steady income, without a stable source of money, you can give up.
However, I get what you were trying to say about the power of hard work to reach big success in our lives because many individuals are from nothing and end up with huge amounts of Bitcoin because of the effort they put into their lives and dreams. However, JJG is still saying the right thing that individuals continue to suffer despite their best efforts due to one or two challenges or to double the amount of money they have available.