I am not an expert, but my belief is that Pegasus does not maintain persistence. While the Wikipedia article claims Pegasus "jailbreaks" the iPhone to maintain

I am not an expert, but my belief is that Pegasus does not maintain persistence. While the Wikipedia article claims Pegasus "jailbreaks" the iPhone to maintain persistence. Every technical article I've read says that a reboot clears Pegasus (albeit, it is easy to re-infect with a no-click exploit without the user's knowledge). Hopefully, someone more knowledgeable can chime in with citations.