Hi @fsw
Yes, exactly. This is more important when using registration for a meeting or webinar, as customers often use the registration form as a way to pre-screen participants.
If someone were to get past the registration portion and intend to cause disruption in the live session, having the Allow registrants to join from multiple devices option enabled could allow that person to share their unique link with others to join at the same time for a larger disruption. Disabling that option just means that when a registrant joins with their link, they have to leave the meeting or webinar first, before being able to join on another device, such as switching from desktop to mobile.
Hope that helps and please make sure to mark the solution as accepted if this information is what you needed.
