There are some German articles that do talk about it in a bit more detail [0].
It's a mix of reasons 1) Covid grants that delayed bankruptcies, 2) Increase of VAT back to 19% for hospitality industries, 3) Increase in construction costs for construction companies, 4) inflation, 5) disruption in trade
And this is not just traditional industries, even 1 in 10 startups risk bankruptcy. [1]
[0] https://www.tagesschau.de/wirtschaft/konjunktur/studie-insol...
[1] https://www.tagesschau.de/wirtschaft/unternehmen/insolvenzen...