Germany sending more arms to Ukraine is not likely to shift the tide of the war. Ukraine had spent billions and years, procuring and training on Javelins, NLAWs, Israeli small arms, and other NATO weapons. But when war arrived, Ukrainians are now resorting to handing out AKs to civilians like candy to defend Kiev. The Russians are picking up Ukraine's collection of Western equipment like trophies.
How would 1000 Panzerfaust 3s and 500 Stingers help Ukraine? Not in a good way. It only lengthens the war, cause more bloodshed, and end up as more war trophies for the Russians. I would even argue that if Germany even were to gift Leopard 2s and Marders to the Ukrainians, it'll end up the same.