As many have been saying, many basic oils are now fine for most applications, especially with 6 month / 5000 mile ocis. That's what advancements in engines, engine oils and competition do for you.
At the same time, the oil manufacturer's need us to buy more expensive oils because ~$12 for PYB, VWB, QSGB is half what they could be getting. All manufacturer's in every line of business want to upsell value whether real or perceived to the consumer.
Selectively releasing information across the range of oils to optimize what they sell overall is precisely what is in their interest. The big manufacturer's are not going to release all the information.
If they released all the information they had, then two things would happen:
1) It would give the competition more marketing ammunition
2) It would lead most of the oil nerds to buy the cheapest oils
They are probably more worried about 1) than 2). For those who are really interested in the details, perhaps approach the smaller manufacturers directly who would love to get a foothold in the nerd market.