There was the idea of the multiverse on television well before Rick and Morty.
You have several instances in Star Trek, including the Mirror Universe in TOS. “Mirror, Mirror” aired in 1967 and was one of the first instances of evil versions of people having goatees.
The show Sliders has a portal device and the show is centered around taking portal trips across the multiverse. That started airing in 1995.
Rick and Morty has used a lot of these tropes to make interesting shows, but they are more recycling old ideas in new ways than making new ones from scratch.
There was the idea of the multiverse on television well before Rick and Morty.
You have several instances in Star Trek, including the Mirror Universe in TOS. “Mirror, Mirror” aired in 1967 and was one of the first instances of evil versions of people having goatees.
The show Sliders has a portal device and the show is centered around taking portal trips across the multiverse. That started airing in 1995.
Rick and Morty has used a lot of these tropes to make interesting shows, but they are more recycling old ideas in new ways than making new ones from scratch.