The GDPR doesn't cover processing of personal data "by a natural person in the course of a purely personal or household activity". So I imagine that at least some instances of recording police officers in public are exempt, especially if you don't follow them around or upload the videos to your local police recordings online community. Of course I also wouldn't argue with the people with the batons.
Fun fact: in east eu laws are bent to protect criminals, as they are essentially those in “power”. In Romania GDPR was used as means to threaten investigative journalists (see Rise Project and GDPR). There are other criminally bent laws that predate gdpr. For instance the government used some obscure privacy “concerns” mandated by the eu (not sure which) to remove ALL traffic monitoring cameras. The result is one of the highest road deaths in the EU and naturally easier to bribe traffic police. Organised crime members are also protected by bogus human rights interpretations, where a mobster gets more rights than and old lady stealing an egg for food.