You can save a lot more money, in absolute dollar terms.
20% of 200k is more than 40% of 80k.
People talk about "cost-of-living" like it's some non-negotiable tax that you have to pay to the world. It's true you can't get the same lifestyle at the same price as a low CoL area - no humongous 5 bedroom house with a massive backyard. But it doesn't mean your life has to necessarily suck.