This is information Meta should happily share. But, they haven’t, for whatever reason.
Why?
“It Works!”
We’re reminded repeatedly about the effectiveness of various optimizations. Meta encourages to turn on all Advantage+ Creative enhancements because it has improved results for other advertisers.

We should use Advantage+ Audience to lower Cost Per Result by 33% (based on Meta’s experiments).

It’s not that I don’t believe that these things are generally beneficial. The problem is the complete lack of transparency when it comes to our own results.
We have no idea how much these optimizations help (or don’t help) for a specific campaign, ad set, or ad. We’re supposed to take Meta’s word for it.
You know what? This sucks. And it’s completely unnecessary.
The Solution
Not surprisingly, Meta struggles to get advertisers to buy in due to this lack of transparency. “Take our word for it” isn’t particularly convincing.
There is a stupidly obvious solution. Here are a couple of breakdowns that Meta could provide to help improve trust and faith in these optimizations:
1. A breakdown for targeting: View separate rows for results based on when our requested audience was reached and when Meta moved beyond that group.
2. A breakdown for Advantage+ Creative enhancements: View separate rows for results for our original ad copy and creative and when specific Advantage+ Creative enhancements were applied.
What is the Risk?
Is it really that difficult? What is the risk?
Of course some advertisers will distort small sample size results that supposedly reject these optimizations. But that would hardly be a solid argument against this transparency.
If these enhancements are truly beneficial in most cases (and I don’t doubt that they are), Meta has nothing to lose.
Prove it! Otherwise, they will continue to struggle to convince advertisers to use or believe in many of the best practices Meta promotes.