At least small planes in europe (CS-23) aren't allowed to have humans within an (iirc ~15 degree) cone of them.
This approach here seems to be done with no regards to such regulatory (and well-meant) requirements.
1) This is a powered lift craft, not a plane, so it doesn't even fall under CS-23.
2) There are classes where you're allowed less in exchange for easier certification. If the craft isn't operated commercially and doesn't need to leave national airspace, certification is typically far easier (at least for anything not heavier than a medium SUV).