^Yes, he played characters named Robby in those two films, and they were very similar characters, but that doesn't automatically put them in continuity,
I didn't say it did?
I just raised the question.
Huh? Yes, you raised the question, and that's my answer. You posited the question, "Do you think it puts them in continuity with each other?" and I answered "no" and explained my reasons for that response. Where's the problem?
"Robby The Robot" wasn't an actor, a persona, or anything else of the kind. It was a prop and a costume that was reused in lots of movies and TV shows, nothing other or more than that.
Also this.
This is so obvious that I don't understand why it needs to be pointed out. My point is that "Robby" was
treated by Hollywood filmmakers
as though he were an actor "playing himself." I explicitly phrased it in those terms, not as a literal reality but as the conceit embraced by the filmmakers and television producers employing the character. I've been discussing it all along as a metaphor, so I really don't understand what the objection is.
The point is that sometimes fictional characters transcend the continuity of the works in which they're introduced and can be incorporated into other works without any implication that the continuity of their original work is being included in the package. Robby was a character created for
Forbidden Planet, but he transcended that film and became an independently existing character, a pop culture meme in his own right. And
The Invisible Boy was the first instance of that happening. Robby was the breakout "celebrity" of
Forbidden Planet. If the breakout star had been a human actor, say Anne Francis, the studio would've cast her in other movies in different roles, different character names, like they would do with any star they wanted to cultivate. But in this case, the "star" was a character rather than a performer, so they treated the character
as a performer, and "cast" him in other films under his own famous name.