In 1984 the ratings guidelines changed, so that nudity was no longer allowed broadly but especially in PG and PG-13 stuff. This effected TV as well.
To compensate and continue drawing viewers, as without nudity things became more boring, there was an increase in violence, blood squirting, horror, etc. These things were still pretty fine for general audiences 🤷♀️
I think things would be nicer if we all saw and appreciated more titties and less beheadings or assassinations, but my opinion doesn't really matter I guess. TLDR blame Reagan.