Way off. If a single person has $30k annual salary their federal income tax would be $1,918 (
https://www.dinkytown.net/java/1040-tax-calculator.html)... MN income tax rate is 5.35% of taxable income ahat level which would add another $1k... so less than $3k in total.
Difference is $2,271... so there is most of the source for $200/month of savings.... your miscalculation of income taxes.
DS earns about that but LBYM and easily saves $200/month. He drives a 2016 used car that he got a great deal on and when he had car payments they were about $210/month. He shares a 2-bedroom apt with a roommate... a bit of a dump IMO but it is very affordable. Not what I would want but he makes it work.