Definitely more than 5. I'm a terrible perfectionist and I always found tiny things to bother me. I'm on my final island though now, I resetted for weeks until I got everything I wanted (fruit, airport, rocks...).
Juan. Only Juan.
Utopia, which I got on launch day of 2020! I love that island so much and I've never even considered getting rid of it for a new one, especially considering I barely open it up nowadays.
Iโve only had one island. I was lucky enough to have everything I wanted on my first island. I didnโt reset for airport color or anything. I was fortunate enough to get blue and oranges on my first try. Iโm not sure I wouldโve reset, though, if I didnโt. I was too eager to start playing I didnโt want the introduction phase to take longer than it already was.
I have an island on 2 Switches.
Main Island was started on release day and never reset.
2nd Island on 2nd Console was started 2 weeks later to get the missing fruit. It took 2 resets to get all the fruit. Started the game after that.
Just one from release day. Sometimes I've considered resetting but ultimately decided against it every time. Getting another console wouldn't be an option either since, like @/xara said, it wouldn't be the best decision financially.
I have two islands. I didn't want to restart my original launch day island, so I got myself a Switch Lite and another copy of the game, just so I could have a second island to play around with and reset to my heart's content.
Just the one! Restarting is so tedious in this game that I just have stuck with my island. Plus I kinda like it as is and am still working on it. It hasn't been completed yet.
Four. Three of them became total nightmares to try to tend to after I listened to Isabelleโs โadviceโ to plant some flowers. Those flowers ended up taking over 90% of the free space on my Island and I couldnโt get rid of them fast enough. Iโd dig for two hours to toss them out and the next day the flowers doubled from before. So by the time I restarted for a fourth Island, I refused to listen to Isabelle and this one is my best Island. The rating still went up enough for KK to start playing concerts and I could finally start planning out the different areas I wanted on my Island.
I only have one island. I'm new to the series overall, so I'm not sure how most people play it, but I love the little community I've made...I don't let any villagers move out lol!
Two, but they're practically mirrors of each other. I only restarted because I couldn't change my representative's name and was tired of seeing it. Thought it was going to be more overwhelming than it ended up being, so I'm very happy I did it.
I've currently got 3 islands.
My 1st one is called 'Hazzard' from February 2022. I would never ever restart that one, even though there is no theme and it is by no means perfect, but it was the first time I met my precious Buck so it will always be a special island.
2nd one I started in June 2022, it's also called 'Hazzard', only because there wasn't enough characters to write 'Hazzard County'.
3rd one, I decided to name it something completely different, Sapphire, after my favourite gemstones.
I don't think I would ever have the courage to restart the other two, as I would hate to have to try and catch fish again! Even though I've not completed anything in the museum apart from the fossils!
If I remember correctly, just 3. The first island was Termina when I got the game, the second (and current one) is Newgrounds, and my 2nd island is Neko Isle.