It's not supposed to be a slippery slope. This is where a functioning "Scrum Master" is supposed to tell that person to stop talking and move on to the next person. That never actually happens though, so the next best scenario is light shaming of the guy who talks too long. If you have bad managers or too many people with management anxiety then it can be good to kick them out of the meeting.
I understand that this is how it is supposed to work in theory. But realistically most startups don't (and dare I say shouldn't) have the luxury of a dedicated Scrum Master.
Another thing I don't like is that it relies on humans to do a good job. How do you hire a good Scrum Master if you've never been one yourself? Hires like that are usually hit or miss. What if you need to hire ten of those?
