r/drones - Questions about the UK regulations

I love photography and I'm considering buying a drone to take cinematic footage. I'm mostly interested in natural landscapes generally far away from cities.

In order to make an informed decision I'm going through all the resources relative to the regulations and restrictions currently enforced in UK, especially for the 250g+ category, and I have a few questions.

My first question is about keeping the drone always in your LoS. Now at first I thought that it was about some reasonable request of keeping the drone under your control, since the direction of flying can be different from the frame that is streamed to your controller/phone etc... But to my understanding the rules are quite literal in always keeping LoS, and if the pilot so much sneeze or the drone goes behind a tree for a split second, he is in open violation of the code and should be fined and/or jailed for his irresponsible behaviour. Is my understanding of the LoS rules correct?

More to that, footage like this one or that one (assuming to be) taken in the middle of nowhere, with 500m+ of clear visual in any direction are still very uncool and very illegal because the pilot, who may be a passenger in the car, has no direct LoS and the drone can injure any nonexistent person around there, right?

And what about auto features, is the pilot still supposed to keep LoS? In this footage we can clearly see an example of irresponsible behaviour where the drone is kept in orbit mode whilst the "pilot" is hiking in the middle of nowhere, without keeping LoS with the drone and no apparent aider/observer around. I counted at least six nonexistent children in that brief footage. It could have been carnage there. Should I assume that any automatic feature (waypoints, follow-me, orbit) are very illegal unless the pilot (which is often the subject) keeps staring at the drone all the time?

Second, I have a question about the "legacy" drones. To my understanding, virtually every 250g+ drone currently sold in UK will automatically be classified as OA3 at the end of 2022, even if the exact same model will be sold under the proper category later on. Is that correct? Should I wait for the new models then?

Talking about categories, OA3 drones can only operate 150m+ away from any recreational area (among other things). This, to my understanding includes (but it is not limited to) beaches, natural reserves/point of interests, and natural parks. A lot of the most interesting drone footage are taken from beaches in the early morning hours, with no other soul around and unrestricted visual for kms. Taking a similar footage is now illegal in UK for OA3 drones, right? Conversely, they are legal for OA2 and OA1 drones, right?

If that is the case, what is the general expected use case for OA3 drones? Taking a footage of an empty field with no people, no interesting POI and possibly no trees or other vertical structures that can easily make you lose LoS with the drone? I'm genuinely thinking to viable interesting scenarios, and I'm having an hard time.

Third (fourth?) is a curiosity about the burden of the proof, so unless you are an UK lawyer it's unlikely you can answer me. I can see a large number of videos on youtube that are very likely to be in clear violation with the current UK regulations, like the ones I linked above, but it's impossible to be 100% sure by footage alone.

Let's say that a malicious pilot goes in the middle of nowhere in the early morning and do a number of irresponsible activities (like the footage linked above). Unfortunately, no officer is around to stop this reckless behaviour and the malicious pilot gets away with that, coming back home unpunished. Let's say that in the next days they are so shameless to edit and enhance and have some fun with their footage, publishing it on their personal youtube channel. An officer watches the video, see no clear indication of an observer/another person and the sole person in frame is the yt channel owner (the pilot) and has clearly lost/no LoS with the drone. From a legal perspective, is the onus on the officer who needs to prove that there is no reasonable way that the pilot could have kept LoS for the whole footage even with one or more hypothetical observers, or is the onus on the pilot, who needs to provide all the information, plans, logistics and names of the people involved in any footage upon request?

Now, I know that culturally in the UK there is a general aversion to question the authority, where pointing out how a rule is ridiculous is often identified with a will to ignore it. So I want to specify that I'm not asking this with the intention of "dodging" the rules, but to well understand all the "can" and "can not" before deciding to investing 300 GBP in a drone now or waiting for more reasonable regulations.

To me the situation is very simple, if I can't legally do what I have in mind with a drone, I won't engage in the activity. All I want to know is if I understood the rules well or if I have missed something.

https://skydanceimaging.com/r-drones-questions-about-the-uk-regulations/