I think adult websites rarely if ever do this voluntarily of their own accord. Age verification is usually the result of laws being passed in specific jurisdictions (e.g. some US states)
[Those who don’t] profile your preferences to be sold.
Not something where I’d rely on trust alone. The same strategies used for sfw browsing would pretty much apply to nsfw as well (e.g. VPN w/ killswitch + a reasonably private browser in private browsing mode + ad/tracker/malware blocking + some fingerprinting mitigations)
While there is nothing wrong with this discussion in itself, let’s avoid direct links to sexually explicit sites for the sake of community members of all ages. Guidelines.