I think this accident could be avoided if off airport landigs would be legal in germany, and helicopters pilots would have a chance to train it.
To be honest I think this is irrelevant. Most flight schools in Germany have a special permission to carry out training off-airfield to cover syllabus exercises like this.
This is about the fundamentals of what is and what isn’t a safe approach. Steep approaches should be taught along with their hazards; along with limited power; and over-pitching; and approaching an off-field site with particular caution. An accident like this simply need not happen: it shows either lack of training or a lack of judgement. Or both.
4-up in an R44 coming in like that: completely inept. You are almost certain to run out of power and over-pitch. And if it turns out the pilot was PPL and carrying fare-paying passengers I hope he goes to jail.