This, my guess is OpenAI wised up after r1 and put safeguards in place for o3 that it didn't have for o1, hence the delay.
DeepSeek-R1 0528 performs almost as well as o3 in AI quality benchmarks. So, either OpenAI didn't restrict access, DeepSeek wasn't using OpenAI's output, or using OpenAI's output doesn't have a material impact in DeepSeek's performance.
https://artificialanalysis.ai/?models=gpt-4-1%2Co4-mini%2Co3...
I am not at all surprised, the CCP views AI race as absolutely critical for their own survival...
EQBench, another "slop benchmark" from the same author, is equally dubious, as is most of his work, e.g. antislop sampler which is trying to solve an NLP task in a programmatic manner.
"Follow the money."
Businesses are pouring money into the OpenAI API. This is your biggest clue.