Why do you think rolling back any of those hard-won regulations is a good idea?
John Oliver covered this two years ago: https://youtu.be/IhO1FcjDMV4
https://www.propublica.org/search?qss=meatpacking
I'm not sure if ProPublica has a free, public dataset on meatpacking plants but they generally have datasets that you can purchase that pertain to particular areas of reporting: Medicare and Medicaid overbilling / fraud; repeated pollution violators who keep paying fines instead of stopping polluting; etc. If anyone knows of a dataset on meatpacking plants, health and/or safety violations, etc. please do share the link to the dataset.
The argument that more pay & benefits for these workers will make meat more expensive is also nothing but a scare tactic. There is already so much automation that the increased cost will hardly be noticeable when it is distributed among purchasing units at the consumer end.
Since the jungle was published, more recent research has been published to show that simply having a meatpacking or butcher factory in the community causes more violent crime, sexual assault, and drug addiction.
https://pubmed.ncbi.nlm.nih.gov/34231439/ - "The Psychological Impact of Slaughterhouse Employment: A Systematic Literature Review "
And how do you need to be to want kids working in anything before they completed their education (minus a couple easy summer jobs). Some American legislators are scum.