We don't need the super-high efficacy numbers (>90%) that the other vaccines are reporting for this to stop the virus. Typical flu vaccines are ~ 50%, I think the Oxford vaccine's results show that they've achieved this.
The efficacy does not need to be super-high, provided enough people decide to actually go get vaccinated, and the percentage of skeptical people seems to be quite high.
Plus, any given vaccinated individual would have to rely less on others being vaccinated as well.
But I am grateful that vaccines got developed and tested so quickly anyway.
Yes I think they only need to hit 50% for approval. Conservatively they were getting 62% as I recall and the 'experimental endpoint' dose got them to 90%.
The Oxford vaccine is far cheaper (15x) and easier to store so long term it has a lot of competitive advantages.