There are many reasons that German support for development funding has tailed off in the last half-decade. From the Covid-19 pandemic to Russia’s full-scale invasion of Ukraine to U.S. friction with NATO, the feeling has become entrenched that Germany, the world’s third-wealthiest country, simply can’t spare the money.
If anything, those notions are engineered and promoted by the powers that be (capital) who don’t want to pay up as usual. We are a wealthy country with a (for European standards) huge amount of billionaires. Which is where that wealth is.