Good basic thinking basically we should not spend money carelessly, we need to detect the needs that may come into our lives in the future, actually in life there will definitely come problems and many of the problems need money to solve them, therefore it is important to set aside our money to save, as an emergency fund or whatever it is, in fact when we have money every problem that comes can be easily solved or not worry about money problems when problems come into our lives.
But on the other hand, besides saving, we need to look at the gap between needs and income, if our income is not sufficient, the solution is not only to save or invest but how to increase income to cover needs so that we can have money for emergency funds and invest.
It is true that spending money carelessly is a problem, but at the same time people are keep forcing the regular people to live frugal life instead of seeing the real problem; companies becoming greedier.
Do not drink starbucks every morning, do not get your avocado toast, do not buy the new iphone, do not go to a vacation you can't afford, do not get all the subscriptions, do not get ... and so forth and so forth while the rich guy just spends 10 billion to shoot himself to space, I am sorry but wtf is wrong with people that we are taking the last ounce of happiness life provides to these low to mid level income people, and not looking at the reality that corporations make tens of billions of profit while not giving their workers any proper raise? That is the real problem.
Wages are way too low right now, and as long as that is not fixed, you will get poorer and poorer, eventually they will tell you that eating three times a day is bad, and you should eat twice, because that is what you will be able to afford anyway with the money these companies pay us.
Yes that's true too, but we can't look there, look at the side of billionaires who have a harder struggle when building their wealth, they are more willing to spend money to build businesses so that they get a lot of income and employ many people who are standardized in salary, and I think they also went through something like that before becoming billionaires who can spend money easily today, so it's not balanced to look that way if we are their workers today.
I agree with your last paragraph that today's salaries are too low to make ends meet, due to inflation and a bad monetary system both in the labor force that makes it very difficult for us to save most of our income, hence many of us have two or even more jobs to be able to save and invest.