I think the article is saying that had he received a loan at a 4% rate for 25 years he would paid the same amount toward the bill as he is currently doing for l

I think the article is saying that had he received a loan at a 4% rate for 25 years he would paid the same amount toward the bill as he is currently doing for loans at a 7.25% rate with loan forgiveness at the end. The 4% is a hypothetical rate, not a real one. Though he did have at least one student loan at a rate of less than 5%. Most student loans are made up of smaller loans. For example, my wife's "student loan" is $100k, but it is made up of 8 loans of 4k to 30k with varying interest rates of 3% to 6.5%. Rates increase every couple of years. To be clear, federal loans are fixed rate loans, but each year you are in school, you may incur new, higher rate loans than the year before.