I did some research when OnlyFans threatened to cut off all adult content, because I was curious as to how such a company could seem to be pulling in so much money -- and in doing that research I saw just how much they were making off your neighbors, the guys you may be working with, and men you see on the highway or walking around in your local box store.
To put it bluntly, sex sells and it always has, going back to the days when young men had pinup photos of Marilyn Monroe. The primary difference is that it's now online for most anyone to access, but think about the late 1980s just to pick a reference point: Print magazines like Playboy, Penthouse and Hustler were popular, most every city had an "adult bookstore" and/or strip club, and larger cities had multiple. Places like truck stops openly advertised "peep shows" and their adult shops on billboards along the interstate. Cut to 2023 and all those things have more or less moved to the internet and it's been that way for some years. OnlyFans has been a real boon because it's kind of a win/win. The models who place their content on that site get more $$ than they'd make working through a traditional adult film studio, while people who subscribe pay a relatively small amount of money to follow the models they like best, see all their videos and content, and can even get specialized stuff done just for them by those same actors for a small fee. None of this is a secret, even NPR did a full hour about it several months back, including interviews with adult film stars who once worked for traditional studios but now feature their own content online, etc.
It's a multibillion dollar business, with some individual content creators' channels having the same number of viewers as a medium sized sports arena. Many of the content creators may make more than you do. Some of the channels may have more cume than most radio stations.
That said, this isn't just the case with adult content. There are many, many people who make a very handsome living just by posting (non-adult) content on social media sites like Instagram and YouTube. There are numerous stories of people who liked to travel, for instance, and they started posting photos and details from their travels on social media. They garnered a ton of followers and posted lots of original content so they got $$ from the social media sites where they were posting. Next, they started getting offers for sponsorships from airlines, hotel chains and other travel-related companies so now traveling and posting about it (and giving shoutouts to their sponsors) has become their sole source of income. There are others who are into wellness and bodybuilding. Again, they posted lots of videos and content documenting their fitness journey, they built up a thousands of followers which meant they were earning serious $$ from the social media sites, then they got sponsorships for things like the supplements they use, the gym clothing they wear, their hair products, etc. and they didn't need a "regular" job...And are making more than many who have traditional 9-5 positions.
As for any of this being on radio, even if it were legal to run on the airwaves I don't see it ever happening. What Stern was able to get away with was probably as far as it could ever go, and as BigA mentioned, Stern got fined.
I don't think anyone would seriously try to emulate what Howard Stern did back in the day. Radio is a much different business now, the days of "shock jocks" and even traditional "morning zoo" formats have passed and while there are some who've tried to be like Stern, the majority have fizzled out or been dropped by their employers. Keep in mind as well that the stuff that was considered cutting edge and "shocking" back when Stern was doing it, would probably be considered relatively tame by today's standards, so you'd need to keep pushing the boundaries and the envelope more and more, which could get one into trouble. Also keep in mind that the standards of decency and what's PC and acceptable have changed. Some of the bits and comments that may have been funny and laughable back when Stern did them would be cringeworthy today, and may even garner HR complaints if someone tried to listen to them in the workplace, etc.