In my opinion it is obvious and should be uncontroversial that some environmental regulations work and are great and should if anything be reinforced, while other environmental regulations do more harm than good and need to be reigned in or eliminated. Turning "environmental regulation" into a unified bloc that must be either supported or opposed in totality is a manipulative political maneuver and it should be force…
I also don't agree on the principle that regulations are "harmful" or "helpful." Rather, you have to define who the regulation harms, and who it helps. For example antitrust enforcement harms shareholders and some employees of very large firms, but it helps many employees and arguably improves the landscape for competition between many smaller firms. So whether a regulation is preferable comes down to values.
In the case of leaded gas, it harms basically everybody, but it helps fuel companies, so it was an easy thing to change.