I tried to switch to iOS when my pixel 3xl died. I gave up after 24hrs and bought a Pixel 6Pro.
Every time I tried to do something on the iPhone, or find a comparable app, it either couldn't be done, or needed an app with an ongoing paid subscription. It was infuriating. Paying one time for an app is one thing. I don't need to be spending 10s of dollars or a month in perpetuity just to use some apps on my phone when I can get the same functionality free, or for a smaller one time payment elsewhere.
When I think of photo sync, automatic is part of it. What use is having to manually start a sync process? Even worse, you have to manually choose which photos to sync on iOS - it won't given you access to "all photos" as a default.
On android, I can configure all sorts of automatic sync.
For example, all photos I take are instantly synced to my home server, instantly.
Videos wait until I'm on WiFi.
Photos taken with a different camera app wait until WiFi.
Other photos, videos, downloads, etc, wait until WiFi.
With iOS, I can't even auto sync ANY of them.
iOS doesn't permit any app direct access to all photos because of how it stores images.
I switched from Android to iPhone a month ago and the Nextcloud app can definitely access & sync all photos & videos just fine.
So far I have not noticed any problems with background sync but I do also open the Nextcloud app frequently so that might have something to do with it. I guess a workaround could be to set up a shortcut which opens Nextcloud whenever the phone is connected to a charger during the night, for example.
Lastly I just want to add that it isn’t all sunshine and rainbows on Android either. From my own experience photo sync never worked reliably on whichever phone I was using (Huawei, LG, Samsung, Google, Microsoft, …). And let’s not forget that each manufacturer is also trying to push their own gallery & backup solution to lock you in. Even worse, some manufacturers like Microsoft have this mishmash where you have OneDrive for photo sync but then also Google Photos which you can’t uninstall and keeps begging you to please back up all your stuff and then pay for more storage. It’s the same BS as Apple with their iCloud tbh.
My experience is directly the opposite. Bought an iPhone 12 Mini after Pixel 3XL died. Granted, I was already using a Macbook for a long time. Lotta things I’d been trying to get working, using things like KDE Connect instantly became automatic.
I’ve seen people actually get job done on phones, but that’s never been the case to me. To me the phone should ideally be an extension of my desktop. I’d been doing that with Chrome+Pixel for a while. But iPhone unlocked much more of macOS for me