Things are smooth indeed. Without real opposition, Germany can further drag the continent down the stagnation and economic strangulation through austerity only it benefits from paths as it pleases.
I have heard the opposite: that the United Kingdom was, as a rule, an important ally for the economic policies favoured by Germany and others. E.g., “So far the following EU countries have announced that they oppose Eurobonds: Germany, United Kingdom, Finland and the Netherlands.” on p. 186 in Schäfer 2012 = vol. 9.2 in EJCE = https://www.researchgate.net/publication/255726169_The_Sover...
Further more, the UK was an important net contributor.
So I think, on the whole, Brexit was bad for Germany.
Germany has pushed Britain out of the EU by allowing more than one million people in, at a time when the UK had a sensitive debate around the very issue that Germany created along with Russia. Russia pushed, Germany pulled. After that Germany has threatened countries with sanctions if they didnt agree to taking in the very people it welcomed against the wishes of member states. It knew exactly what it did, and it did it to push Britain out of the Union because it found it to its advantage.
Totally agree. I think also the Scandinavian countries were sad to see the UK go, as someone else has mentioned in another comment, it was a counterweight to German/French hegemony.
Further more, the UK was an important net contributor.
So I think, on the whole, Brexit was bad for Germany.