Users who want to sync bookmarks across devices will also want to sync any extensions they have installed.
I have installed a number of extensions via the Chrome store, including a password manager, page zipper, Go Back With Backspace and IBA optout. These hugely assist workflow by speeding up login, reducing ‘next page’ clicks etc. It would be a major irritation to me to have to install these on multiple devices, or remember to add a new one, when it could be achieved via automatic sync.
New users may be prepared to install the extensions once in order to judge the ‘before’ and ‘after’ experience. However, even if they prefer Brave, they may stick with the old browser as the advantage of automatic extension syncing is significant.