I think you forgot to click the “inflation adjusted” checkbox. The real rate of return is closer to ~7%. Also caveat emptor - past performance is no guarantee of future results.
I think that’s the point. A projected savings balance is misleading without considering inflation, so if the calculator doesn’t make an explicit adjustment for it then there ought to be an implicit adjustment in the rate of return assumption.
Projecting historically low inflation is no less reckless than ignoring it. Imo, you're better off looking at absolute returns and tweaking your expectations based in inflation as itnhaopens.