There is a incorrect assumption - you can't take out 4% if you are only assuming at 5% rate of return. The 4% number comes from an assumption of 8.5% (long te

There is a incorrect assumption - you can't take out 4% if you are only assuming at 5% rate of return. The 4% number comes from an assumption of 8.5% (long term stock market returns) minus inflation minus taxes. So in your 5% assumption, this means you can only take out 0.5% or less. But the article is overall directionally right. The less you spend on shiny, the less you need, and therefore the less you need for retirement.