Star Wars doesn’t have to be Cocomelon to still be for kids. It can still have some level of maturity while not being on the same level of maturity as media made for adults.
Yeah, I’m of the opinion that Star Wars was always made with kids in mind. We know for a fact that Lucas was heavily inspired by the Flash Gordon serials of his youth. The crucial difference is that the OT (and probably ROTS) were mature kids’ movies (that could also be enjoyed by adults), whereas TPM and AOTC were more lowbrow.
WRT Owen/Beru’s corpses specifically, keep in mind that kids’ media back in the day was less watered-down than the stuff nowadays. I imagine that shot would have overall been considered acceptable, especially since it’s short and a relatively insignificant part of the film.