In the mid 80's, WWF's Rock 'N' Wrestling evolved the WWF from male niche entertainment to family entertainment and, eventually, professional wrestling as a whole from an teen/adult thing to a "family" thing as even promoters who already had, say, a large female audience, tried to imitate it.
Despite what its name implies, Total Nonstop Action had plenty of T&A on display when it first started, along with a hearty serving of hardcoreGimmick Matches and a general grungy atmosphere meant to be appeal to more mature audiences than WWE's. After they got a deal with Fox Sports Net though, TNA went family friendly, from "Sex Appeal" to "Six Appeal" with its six sided ring. Their pay per views were not quite as toned down and the atmosphere of the product got much heavier after leaving Fox but it has never descended to the level of the early days.
WWE shifted their free TV programming from a TV-14 rating to TV-PG starting in 2008; this was done to help distance the current product from the "anything goes" Attitude Era (especially in light of the Chris Benoit tragedy and the steroid scandals brought to light by a Sports Illustrated article in 2006 that named names), due to the company realizing that they are able to fit John Cena in the same kid-friendly superhero role that Hulk Hogan played in the '80s, as well as to help attract new advertisers (and a younger demographic). It's also been speculated that the shift was to accommodate Linda McMahon's run for the US Senate; an attempt to portray her as a CEO of a "family-friendly" organization, even going so far as to attempt to block all videos on YouTube taken during the Attitude Era. Nevertheless, when the campaign failed, it didn't result into the TV-14 rebound some IWC fans were hoping for. Which may or may not cast doubt on if this was ever really a factor at all. Though teasing a few times that it might be getting edgy again, so far WWE hasn't followed through, and probably aren't going to anytime soon.
The revived "ECW". It was used more as a launching platform for up and coming wrestlers and a place to dump useless ones.
John Cena: "I know that kids are watching my every move and there are a lot of parents know their kids look up to me and [...] I kind of live by the motto — 'Hustle, Loyalty, Respect'. If someone is out of line, I think instead of giving them an FU, it's better to give them an attitude adjustment."
The F-U was also a Take That to the F-5 finishing move of Brock Lesnar. Officially, one of the reasons for changing the name was that the reference was beyond outdated, as a lot of Cena's present fanbase wasn't even toilet-trained when Lesnar was first wrestling.
When Mick Foley hit legitimate main event status in late 1998, he traded in a lot of the more sado-masochistic elements of his gimmick for a more humorous approach (which Triple H referred to as a "human muppet") that included a sock puppet and a more child-like demeanor. He, however, still retained bits of his Crazy Awesome tolerance for pain which, combined with his new more innocent behavior turned into The Woobie of the WWF.
Prior to coming to the WWF, The Sheepherders were one of the most hardcore tag teams in pro wrestling. Upon their arrival, Butch Miller and Luke Williams changed their name to the Bushwhackers, became faces, and played their brawling style more for laughs than for heat.
The entire CHIKARA wrestling league is built around this. Television production is broken into distinct "seasons", with each season's DVD release being designed as a comic book cover. Several wrestlers are based on video game and comic book characters. There is no swearing whatsoever, to the point where attempts to start a swearing chant by the crowd are shouted down by the rest of the audience. Rule of Funny holds sway, with stunts like holding the first minute or so of a match in slow motion, while another has a wrestler who doesn't like where the match is going, so he pauses and rewinds the match several seconds, starts again, and this time reverses a move he now sees coming.
If a wrestler gets a start in a promotion with a much different target audience before jumping ship to another, which can be said of practically anyone who started of in ultra violence encouraging no language filter CZW who went on to be a Chikara regular. Also can happen in a single promotion if it has different shows with different ratings, such as when Gateway Championship Wrestling decided it was going to discontinue its "adult" shows, meaning everyone now had to clean up for a family audience at all times or when a WWE wrestler moved from TV 14 rated Raw/Heat to PG rated Smackdown/Velocity. Then the whole of the WWE turned PG, except for pay per views up until Hell In A Cell turned pay per view PG too, making all of those continued shows afterward lighter and softer.