Self defence lessons protected me from an attempted rape at age 19.
I was interviewed by police and Dame Janet Smith as part of operation Yew tree 4 years ago and was genuinely shocked when I realised that, upon reflection, In all likelihood I escaped a predator because of 6 PE lessons 4 years previous. Dame Janet repeatedly asked why I had lain on the floor and screamed - why didn't I just go with him? It was because I was told never to let myself be taken into a private place with any one who I suspected might be a predator.
We weren't taught to fight, we were taught to, and practised screaming, crumpling to the floor and 'being floppy' so you can't easily be carried away, to bite anything possible (again practising). It sounds ridiculous but it was quite fun at the time and it worked when I needed it, and felt second nature.
I have taught both my kids the same techniques.
This wouldn't help anyone attacked outdoors/away from other people but it is useful in some circumstances.