A long time ago, I created a tag synonym between "roomba" and "irobot-create". Meaning that anytime someone tagged a question as "roomba", it automatically got re-worded as "irobot-create". That might have made sense 6 years ago. But since then, iRobot has come out with the Create2, and will soon release the Create3. With each successive release, the Create is less and less "just a Roomba". So I think it is time to delete the synonym.
Unfortunately, that means there will be about 50 questions with the "roomba" tag that might need to be manually edited. Of course some of these could legitimately be about the Roomba and not Create. So this will require some amount of manual effort.