Vox - Study: anti-Black hiring discrimination is as prevalent today as it was in 1989

Which of the following are conclusions from this article?

https://www.vox.com/identities/2017/9/18/16307782/study-racism-jobs

1. The authors were only able to include published articles in their meta-analysis since unpublished articles can't be found anywhere, so there may be publication bias from never including unpublished papers.
2. The meta-analysis only included 24 studies, and the small sample size may make it difficult to detect a change in anti-black hiring practices.
3. There may have been large reductions in anti-Black hiring prior to the study's start date due to anti-discrimination laws and reductions in average racial prejudice.
4. Anti-Black hiring discrimination has not improved since the 1970s, and there's only been slight improvement for Latino workers.