I don’t think it is - it’s the natural conclusion of his character path. Remember Yoda’s words in Ep I about the paths to the Dark Side - fear, anger, and hatred. Palpatine was driven by hatred. Ben was driven by anger. Anakin was driven by fear - and so is Luke, and specifically fear of losing those closest to them. It was fear of losing Padme that drove Anakin into Palpatine’s clutches. It was fear of losing his friends that made Luke rush off to confront Vader at Cloud City before he was ready, fear of Leia turning to the Dark Side that nearly drove him to kill Vader in the Emperor’s throne room, and fear of losing Ben that lead him to nearly strike him down as well.
And so he exiles himself, because even if he found someone to pass the torch to, he’s afraid that he’d lose them as well. And in the end, he protects his friends by defeating his fear, the same way he did when he refused to strike down Vader. He doesn’t save the galaxy in ROTJ by defeating his father, but by redeeming him, and in TLJ he doesn’t save his friends by defeating Ben, but by showing him that aggression is not the path to victory.
Not for ANH. No one was prepared for how big the action figure market was going to be - Fox let George have the rights for next to nothing, he sold them to Kenner for even less, and Kenner didn’t have anything ready for Christmas and had to sell certificates that could be traded for figures when they were ready.
For ESB, sure, they were dipping their toes into “add characters we can sell at ToysRUs”, and by ROTJ it was in full swing.
…the ambitious Senator Palpatine caused himself to be elected President of the Republic. He promised to reunite the disaffected among the people and to restore the remembered glory of the Republic.
Once secure in office he declared himself Emperor, shutting himself away from the populace. Soon he was controlled by the very assistants and boot-lickers he had appointed to high office, and the cries of the people for justice did not reach his ears.
Nothing about old & infirm, more like willing to be a puppet as long as he got to call himself Emperor. And it’s not really supported by the single mention of the Emperor in the movie, in the conference room scene. Tarkin announces the Emperor has just dissolved the Imperial Senate, and General Tagge replies “That’s impossible, how will the Emperor maintain control without the bureaucracy?” They could just been playing lip service to the fiction that the Emperor is actually in control, not being controlled by the governors, but the more obvious conclusion is that he’s really running things.
And of course by the 53 minute mark in ESB, when the Emperor gives instructions to Vader, it’s clear the novelization was utterly wrong, and the Emperor is fully in control of the Empire.
I can still remember the massive anticipation among us kids about new action figures pre-Empire. Boba Fett could only be obtained by mailing in proof of purchases from other action figures. Then it had to be redesigned before release so the the rocket didn’t shoot. 6-8 weeks ended up being much longer.
Anybody who says the Holiday Special was a failure is totally missing the frenzy around obtaining Boba Fett. Every kid had to have one, and the only way to get it was to buy four other figures.
During this period there was also a stream of releases of background characters from the cantina, and droids from the Jawa crawler.
Oh yeah. I even remember carefully peeling back the sticker on the back of the Boba Fett package to see the original missile launcher instructions. But my point was that ROTJ was the first time they introduced characters with the main/sole intention of selling them as toys. I don’t think Boba Fett was introduced for that reason, he was more the inspiration for it.