Things will change.
Alec Guinness was vocal about not liking Star Wars, even said people who liked it were of low intelligence. Perhaps when all this kind of stuff blows over -- and it will -- figures of her character will start to be made.
I can't imagine them never making a Cara Dune figure. I mean, Mando's heyday was likely the first two seasons, and if season 3 isn't a step up, then there will be even more motivation to go back to the well.
Don't underestimate the ability of Disney to be petty. Unless Mando totally tanks in season 3, there's no way Cara comes back even for toys. Mando season 3 doesn't even need to be a step up, it just needs to not fall flat, which it won't. Viewership probably goes down no matter what with Grogu gone. Any dip in eyeballs or dollars will be chalked up to that.
As far as Alec Guinness, that's a different set of circumstances. I kind of liken it to Mark Hamill calling his character Jake Skywalker and ripping on Last Jedi during the press tour, and being told to shut up by Disney. I'd imagine that's what would have happened with Guinness if he were alive and part of the sequels while making those comments.
It's different with Carano. She's a politically charged person in a politically charged world, who was at odds with the politically charged people who signed her checks. She would have been fired before season 2 if Favreau and Pascal, two people on the other side of the political spectrum from her, didn't go to bat for her. Rian Johnson called people who didn't like TLJ toxic man babies and he still has some kind of movies in development down the line. That's more what Guinness did, which is very different from Gina. She won't be back. Especially not with Bo-Katan and Ahsoka Tano ready to replace her as the female lead of Star Wars.
Could happen sooner than some might think if Kennedy gets ousted this year. Favreau is the master of keeping secrets. Imagine if Cara Dune makes a surprise return to the show? The internet would explode.
There have been people saying Kennedy was going to get fired for three years now, dating back to the polarized divide on Last Jedi. That the damage done to the brand and fanbase would cost her. Then she was going to get fired because Solo underperformed at the box office. Then she was going to get fired because Rise of Skywalker was a total mess and failed to fix the damage done from TLJ. Then she was going to get fired because Star Wars was falling so far behind Marvel. There's been a million reasons she was going to get the axe and nothing happened.
I'll believe it when I see it, but I doubt she's going anywhere. Not with Mandalorian and Clone Wars having turned the franchise around.