I think it's more than a bit irritating. I don't use the iCloud, and I don't want to sync anything. I don't see anyway around the annoying popups. Aside from a couple Macs I own no Apple products.
I'm quite annoyed with Apple. When Big Sur came out, I realized that I would soon have four obsolete Apple products on my hands.
One of these was the basic 2014 Mini and Apple allows me to put Big Sur on it, but it was a big mistake. As this machine comes with a whopping 4 gigs of memory, which is enough to run a browser with one or two tabs open. Anything more than that starts the thrashing. Life is too short. Of course, this Mini cannot be altered by me in any reasonable way, so I'm stuck with something of very limited use.
By accident, I upgraded the OS again to Monterrey, which largely seems like Big Sur except for the iCloud nonsense. I meant only to upgrade Safari. I thought I'd unchecked the OS, but I'm stuck. I either reinstall Catalina or Big Sur or wait till someone figures out a way around this.
I've already replaced a 2012 Mini that I kept on my desk with an impressive minipc that can be upgraded easily by me, and I put Windows11. To my surprise, it's not bad. I've hated the previous versions of Windows.