As one who has sent quite a few early solos I have every sympathy will all involved in this accident.
That said I feel the primary cause of this accident was the fact that the student pilot did not recognise the signs of an approaching stall, the symptoms of the full stall and failed to recover from the stall. This, in my opinion, points to a lack of training. There may well have been exacerbating circumstances but I do feel that if the student has been comprehensively trained in stall recognition the likelihood of him/her actually stalling the a/c is fairly remote.
Years ago spinning was part of the PPL syllabus but this was withdrawn and replaced with "Slow Flight" awareness. I always used to think when we taught spinning that even if the only thing the student learned from this exercise was "I will never let the aircraft get to that stage" that he/she had learned somethinh useful. That said, there were accidents whilst spin training was being conducted.
When I teach stall recovery I introduce the element of a distraction factor and include in the brief the fact that the time when you might get close to stall by mistake is when you get distracted by, for example, another aircraft in close proximity.
Like the Swiss Cheese model the accident occurs when all the holes line up. Although ATC may have been a factor in this accident the primary cause was an inadvertant stall near the ground.