Most of the time the issue was dealt with at the station level, the presenter would get replaced for anything from a week to a month depending on what was let through. It was only bad cases that got escalated to fine or repeated incidents that risked licences.
All sorts of shit got banned, we didn't have a PMRC but the government department that was in charge of classifications banned shit but it was always banned after the release. I never played GTA but I got Body Count's first album then it got banned for the song Cop Killer. NWA's album got banned about the same time and then some expert decided banning was silly and they put "Explicit Lyrics" stickers on everything. Games were different they went straight to classifications just like movies. The first game I remember being banned was Phantasmagoria which came on 8 CD's it was before GTA and banned due to graphic horror, but like everything it was banned months after the fact and there was heaps of copies already on the streets. Within twelve months it was available again with a R18+ rating that stopped kids buying it.