What seems to be missing from a lot of the news reports is that the story/image that Samantha Bee was commenting on when she made the comments about Ivanka was that picture of the kids behind chain link fences that was making the rounds and falsely reported as Trumps kid jail, but it turned out was actually taken while Obama was president. So not only were the comments disgusting, but she was making false claims at the same time about Trump. She should have been directing her outrage against Obama.
The other thing is that while Rosanne's tweet was obviously in poor taste and could be claimed to be racist, ignoring that Bush was often compared to a Chimp and Trump to an Orangutang. Historically blacks have been compared to monkeys such comparisons may not always be in fact racism, it could just be an insult. Rosanne made the comment by herself spur of the moment in a tweet. Samantha's comments were scripted and reviewed during editing of the show, and there had to be a whole lot of people that saw it prior to it airing, not a spur of the moment comment that should not have been made.
Plus putting all that aside, free speech, doesn't mean they can't be fired, but for one I'm sick of all the outrage. If you don't like what someone says don't listen.