I say..it depends. WWE goes where society takes them. The 1990's, while being the best era of television, it was also the craziest. MTV, E! and other stations had girls making out all the time. Howard Stern was on cable and he was 10x crazier then he is now. WWE was no different with DX in the mix, but as society changed and networks forced to calm their panties due to the children, everything became different. WWE started to lose their hardcore fans (possibly due to internet) and decided their new target audience would be children. The adult males may not watch wrestling, but their kids still did/started to. 

So as I said, TV-14 may return only if society allows it. It wasn't that bad when you think about it, but these days you can't go around saying "suck it" you'll be slapped with a sexual harassment suit. Ha