The easier way of phrasing it is "you can't record in public, except in certain circumstances". Those certain circumstances just happen to encompass most things reasonable people want to do.

In Europe there is very much an expectation of privacy in public. But that expectation is not absolute, it competes with various other rights and public interests.

For example you can make street photography without blurred faces, because art trumps privacy in this instance. If you start making photos of individuals instead of areas then privacy wins out again and you need consent. A surveillance camera is not creating art, so it doesn't have that excuse going for it and needs a really good reason to be pointed at public areas (and "I fear someone's going to break into my private home" is generally not a good enough reason). And even if you can set up the surveillance camera, operating it requires complying with the GDPR, which has a lot to say on that topic

There's a difference between taking a photo of eg. random people on the street (eg. trying to show someone that there's a big crowd at the bus station) and recording 24/7 the same bus station. A single photo held by a single person makes it hard to establish movement patterns etc. for those people, while a 24/7 recording can be used for creating a database of all those people coming and leaving.

There are many nuances in privacy law, not just pertaining to photo vs. 24/7 recording, but also expectation of privacy, intent, etc. Taking a photo of some random touristy area with people there is ok, singling out a person is not. Same for eg. taking a panoramic shot of a city where someone just happens to be undressing by the window in one of the buildings in the photo, vs using a telephoto lens pointed at that persons window... so, were you taking a touristy photo vs intending to violate their privacy.

Same nuances, mostly regarding intent appear in other laws too.. you can walk in public, you can stand in a public location, you can work the same shift as your coworker and walk the same path as them, since you both finished work at at the same time. But under slightly different circumstances that same "walking down a public road" or "standing in a public location" can be interpreted as eg. stalking if done with different intent.

That's why there are signs at every store entrance about video surveillance, even though it's private property, they must give info to customers who the contact person for the recording is and they need to have some kind of a retention policy defined for those recordings, and even then they cannot record in areas where people expect privacy (bathrooms, dressing rooms, etc.).

So yeah, taking a random photo of your street is not problematic, since it's "random" and done for other reasons (eg. tourism) while recording 24/7 is gathering enough data to be possibly problematic. Some streets (eg highways) are under video surveillance, but there are signs saying that when you enter the highway: https://maps.app.goo.gl/Mj3GjA7m8BLwUfs77

Short answer is its complicated and will vary from member state to member state. My parental unit had a dispute with neighbor over where his camera is pointed and filed some motion to see what he does with it ( 'not making a database' part ), but the law was mostly toothless as the enforcement of it lacked. On the other hand, the dispute part of the real estate was handed real toot sweet, because everyone and their mother cares about outcomes in those.

tldr: I wish I could tell you there is a simple tldr