From the USA this look nuts - why mandate O2 to be there to look at but not use?
OTOH - I just flew a 3,000 mile delivery with a lot of time at 9500 and 11500. I would have used O2 if I had it, my pulse-ox was in the mid to high 80s and it was fatiguing. I think I was better at high altitude flying when I was in my 20s, but maybe not so much anymore.