So how would less regulation around data security (which is the thing that this is about) prevent another Equifax? Remember, you and I are not Equifax's customers, so we have no ability to choose anything in this scenario.
Equifax took care of this possibility by taking advantage of the freedom they had to place binding arbitration clauses in their customer agreements.
Unless you're independently wealthy, taking Equifax on by yourself in court is a non-starter. This, of course, was the point of adding these clauses in the first place.
I don't buy that, mainly because that only works if I can afford to sue those doing wrong. Most people cannot. Hence, why the government is there: to uphold these laws, and use everyone's collective resources to do that.
1) Sophisticated corporations have developed legal loopholes to eliminate their vulnerability to class actions. Wells Fargo used this tactic to have the lawsuits about the fraudulent accounts it created dismissed [1]. Equifax may or may not be able to benefit from similar provisions (they had one on their website terms of use, which their twitter said didn't apply to the breach as they were getting PR flak for it).
In a move you doubtless approve of, the regulation that would have restored consumer access to the legal system was repealed [2].
2) Money damages in a class action lawsuits aren't going to really make the victims of the Equifax breach whole. Valuing your leaked personal data is very difficult, as is proving that an identity theft was performed with information leaked from a particular source, and both of these will work in Equifax's favor in court. The data has been leaked, and a lawsuit isn't going to put it back into a bottle, nor is it likely to financially chastise Equifax adequately.
Are you going to start lobby to make it illegal for companies to put anti-class action clauses in their ToS? Are you going to lobby to make it illegal for a company to force mandatory binding arbitration on their customers? If not, then you're just trying to have your cake and eat it too. You're trying to keep the government from punishing wrongdoing, and trying to keep people from the very few remedies they have.