Founders - they don't trust the people they have hired so they micromanage. They're not particularly inspiring.
Lack of cross-functional teams - in Product & Tech there are a lot of teams but many are understaffed or incomplete. Don't expect truly cross-functional teams, or skills like Developers, Designers, Agile Coaches, Tech Leads, Engineering Managers to be available at the level necessary. That also results in many people playing multiple roles or being spread thin. Some roles are very demanding and there are high expectations but there's not much reward (benefits have been cut, salaries are not always in-band or to industry standard).
Office - there are a few offices in Berlin and they are quite different. If you're unfortunate enough to be in K72, forget about a comfortable work environment. In pre-COVID times there were not enough desks for new joiners and everyone is cramped on top of each other, there is not enough meeting rooms. No secure bike storage. R22 is just dull.
Ultimately, it's a chaotic work enviroment that offers no real benefit or reason to work there (aside from the people but you can get nice people at any company).