What do you mean by independent young adult. Is that even possible to be any more?
Yes
I was born into a poor family, single mom with mental illness. I never had air conditioning, we spent many years without a hot water heater lugging water boiled on the stove into a bath tub to wash up. My family drove beaters. Moved out at 14. Dropped out of high school. Spent a few years figuring out my shit. Got an associates at 25 at a community college. Got a job in IT support making 50k... ten years later at 100kish.
Today the same thing can happen but entry level pay is 10-15k higher. Renting just a room is still doable on that entry level pay. Community college costs are still effectively 0 if you have 0 expected family contribution. I did work retail while I was in community college part time, offsetting cost of living expenses only. Avoid education loans at all costs imo, you can't declare bankruptcy and dump them if the worst case scenario happens and a degree is not a guaranteed job.
I never gambled health, safety or finances. I didn't do drugs or get involved in something that could fuck my life too hard. I never spent a dollar I didn't have in the bank unless it was absolutely necessary and still live that way because I grew up knowing how valuable money is, and how much it sucks when you don't have it.
Nowadays even around Boston on public transit lines (no car expense) you can find a studio apartment for 1500/mo with nothing included. Once you're making 60k you can squeak by living alone. You can instead save probably 1k by having roommates/a girlfriend and splitting bills. After five years and two job changes you're gonna be able to bank a lot more money than you'd think.
People want it to be easy to live a high quality lifestyle but it just doesn't work that way. Most people had parents struggling when they were growing up but they still managed to make it. If you get a bachelors degree in a higher quality major like analytics you can make way more money than I do.
One big mistake early and you're fucked though. Babies, major health accidents, lack of dental maintenance all can hose you for a huge portion of your life. If you choose to live near family far away from jobs and opportunities you're fucked. I have a ton of friends with child support payments that eat most of their take home pay.