They were about of administration, because their former investor wanted to make them the big city club, because for a big city like Berlin they didn't really have a consistent big club. Ok, Union Berlin had some good success over the last 5 years. It's the first positive results in years financially.
Yes, they went down, but they were in a relegation battle for 2-3 seasons in a row despite spending big every season. In the end, they had 85% of team changed for this season. And there are 6-7 teams with ambition and the aim to go up in the 2nd Bundesliga. Probably the most competitive of all 2nd league in Europe. Yet there are 2 teams leading the table that were not among the big favorites.
Hertha however want to go up within a few years.
I mean you look the names in the 2nd league, Schalke, Hamburg, Nuremburg, Hannover, Kaiserslautern, Düsseldorf and Hertha, some of them won the champions multiple times or played European cups in the last 10 years.