Depends if you count the cost of statutory health insurance as a de-facto tax, in which case it's closer to 40% again. There's a bit more nuance to this (there's a contribution cap), but if you ever read that taxes in Germany are lower than 40% odds are the speaker is leaving out health insurance.

Aside: The neat thing with the statutory health insurance is of course that they have to pay for your treatment, no matter how fucked up your situation is or how little money you have - but if you're healthy and well-paid it's poor value.