That makes sense given that AMD are already leagues ahead of Nvidia in the most critical areas with the 9070 stuff against the 5070 and 5070Ti. But the 5060 and 5060Ti will have less competition if they don't push the 9060 XT out as soon as possible. Given how small the die is, I think they can take enormous market share with the 16GB variant.
If they CLEARLY market it as such and make it very visible on the box, I don't have an issue with a 9060XT 8GB personally. I don't think they will sell many and AMD likely knows that. I think they're just ensuring everyone is given an option. To me it all comes down to marketing and product placement.