At this point, how can we tell whether AI is improving or it's just reappropriating its users work? It's probably a bit of both. But still, thick milky.
OpenAI's proof is substantially different and I don't think anyone has claimed otherwise. The accusation is that they used the same avenue of attack, and it's an uncommon one, and that makes it suspicious that they may have taken the idea.
This has a few practical implications: First of all, if you are in the target group of the marketing material, be wary. While these things can do non-trivial stuff, the amount of magic is being grossly over-stated. But also, when several of the big results have indeed been reappropriating the work of others; when the companies fail to provide proper attribution (the NS case in particular is laughable) and present the results as the models' own work, that's plagiarism.