Successful centrist coalition talks are a positive sign amid the growing presence of extremist parties on both sides. Germany has failed to prevent economic recession and fix immigration issues, but the solution isn't to let the far-right AfD or far-left BSW snatch the reins of power. If the CDU and CSU wish to maintain a centrist country, they'll have to fix the economy and show voters that they can defend against Russia without hurting the economy.
This coalition isn't trying to retain centrist policies but rather an elitist status quo that has destroyed workers in favor of radical green energy and mass migration agendas. Large portions of the country, most notably the industrial lands of the southwest, have seen voters leave the CDU for the AfD due to economic reasons. Voter discontent will only grow if the ruling regime thinks it can apply old solutions to new problems.