TL;DR Yes, but reality is nuanced, as always.

The recent federal bullshit is a definitely the culmination of decades of industry trying to undo environmental regulations. Moving forward, it's going to take serious efforts and funds to repair and rebuild how much the US EPA and federal sciences were gutted. Some states are actually doing far better. On the environmental side of things, Ohio is actually pretty good. The programs are based on the federal ones and also have more protective limits to some things. Unfortunately, not all states have the resources or programs in place.

To your specific points, treated sewage solids have been spread on ag land for decades. Concentrates animal feeding operations (CAFOs) have been polluting waterways through permit exemptions for decades. A huge issue with land applied sewage solids is PFAS, which is just now publicly coming to light. There are vast deficiencies in the way things have been happening all along that still happened in the "golden era".

Negligent or intentional releases of hazardous waste onto the surface or into waterways has been greatly curtailed across the board. There are going to to be ups and downs in speed due to the reality of investigation and cleanup work, regulatory review time frames, and the thorough nature of the programs. The "fast" version of a facility cleanup that I've been part of, where problems were addressed as they were discovered, still took from 2009 to 2018, then massive reporting efforts that took US EPA 5 years to come back with a final decision.

ETA: Most sites I have worked on in my career have been legacy contamination sites, meaning things happened in tue 50s-80s, and the companies responsible have been purchased 2 or 3 times since (or are entirely defunct). The companies that bought the sites and liabilities generally want to do the right thing and clean up the issues to mitigate human health and environmental risks. They also don't want to go bankrupt in the process, which is part of why things take so long. Environmental work is expensive, and the time frames for cleanup and monitoring can be years to decades to "in perpetuity" for some issues.

I was going to say, especially in this era, "lawful" does not necessarily mean "good," and can often be far from it.