Curious
I would one, be concerned that something that originated from a video game was in reality so many pieces from it would have a chance of occurring in reality. (Such as the mental shutdowns and psychotic breakdowns.) Second, I would be scared of their reactions to the fandom. And lastly, I would be concerned about their safety, since they would most likely be tracked down by the government, and others who have suffered due to the metaverse's actions like shadows and palaces. However, may people I believe would really enjoy having them around so they could help peoples' distorted minds like <spoiler>Masoyoshi Shido, a crooked politician</spoiler>. So overall, I believe that if the Phantom Thieves indeed existed in reality, it would be a very interesting turn of events to say the least.
More curiousity from me.
One, I think that would get more busy because if changes of heart were possible, the public would be all over them. Second, I'd wonder if requests were actually legitimate and not fake and made up. Third, I'm also a bit curious on how the pandemic would effect the shadows in mementos. And lastly, something else would be the world itself. Since all of the persona users are in Japan most of the time, what if there were other persona users in other countries? Would they have groups too? Or would they work solo?