With proper care, they can survive transit from one Mac to another, so long as only Mac technology is used to do so, and so long as both the alias and the target are moved together in the same operation. This is a bit like how dragging binder items between projects, that are interlinked, can break the links if you drag them one by one, but if you drag the whole cluster together, Scrivener can relink everything back together with their new internal IDs in the new project.
What won’t work: cloud sync, FTP, a thumb drive formatted to exFAT or other Win compatible format, SMB file sharing, etc.
Scrivener itself takes things even further, in recognition of the common practical problem of how popular these forms of transit are.
In practice, if one plans their user folder organisation around safe alias usage, or giving Scrivener a chance to heal links whenever switching machines, you should not in practice run into broken links.
I ended up stopping to use import links as the links were fragile, and Illustrator’s link resolution tool was utterly rubbish.
That’s one thing Scrivener does with image links to the disk that should, also with mindfulness of keeping multiple machines similarly organised, result in few cases where links break. But even if they do it’s usually very easy to fix broken images as our fallback is to print the broken path as text. A simple project-wide search and replace can find all broken paths at once.