What you fail to understand is that most people don't make enough to save much of anything, the key to your success is you started out an engineer at 20 yrs old, engineering school is very difficult and expensive, most people do not have what it takes to achieve that, so you started out with 50% disposable income or more to save, that is very different from the 5% for most.
The way the manufacturing jobs went away to China and Mexico, unless you are a doctor, lawyer, engineer, you don't have much of a chance, but you can live in a single wide trailer and work two jobs and maybe have a slightly better chance eventually.
LOL when I was in engineering school in Iowa city, I lived just fine on poverty level spending.
When I got my first job in Chicago in 1962, I lived healthy on $125/month including food, rent and transportation..
Because I drove 15 year old jalopies, looked for bargain clothes on clearance sale, and rented a cheap 1 bedroom apartment.
My colleagues drove new cars, and lived in single family homes, saving probably nothing.
USA has the cheapest food compared to any Western country. And older used cars are very cheap.
But most people want newer cars, fancy furniture, and go on expensive vacations.
Just look at how many new cars are sold each year. Cars can last 15 years. How many people keep them 15 years?
No wonder they have little savings. How much you save depends all on how much below your means you are willing to live.
"Money cannot consistently be made trading every day or every week during the year." ~ Jesse Livermore Trading Rule