No. That's what used to be necessary, before SESTA and FOSTA passed[0]. The whole point of SESTA and FOSTA was to remove that requirement - websites are now liable even if they aren't complicit. Even if they take active efforts to combat sex work on their service, they're still liable if someone manages to use the site for that purpose.
Again, none of this relates to sex trafficking. It applies to consensual sex work.
[0] And even though SESTA and FOSTA aren't signed into law yet, Blumenthal specifically wrote the law to apply retroactively. So once the bills are signed, this lower standard is what will apply.