If the go pro evidence is relevant I would expect it to be admitted.
In both civil and criminal proceedings.
As an example, if Mr Plod pulls over motorcyclist for alleged speeding, and sees a go pro attached to helmet....what do you think will happen to go pro footage ?
If accident in any vehicle, including boat, plane, car.....and go pro footage shows captain, pilot driver was not at controls of vehicle, or was distracted by texting when accident happened, does anyone thing such footage would not be relevant ?
So for me the assertion that all private video footage is just not admissible evidence, in any court of law is just nonsense.