The intricacies of relationships with your partner, friends or family soon after everyone realises that "you know/they know" that you have 'physically' received their presence yet chose to ignore it by minutes/hours or days can and will for some create tensions/problems. You make a number of good examples yourself with regard to the needy types or just those that feel it's their God given right to never be ignored. I also have to deal with feeling "obliged" to respond with immediacy because I'm the one that bought the watch and put myself in the thick of it. It's part and parcel of owning and wearing it, but it does come at a price.
Oh no doubt it can create problems and tensions. But at 48, I recall what it was like before cell phones and I can tell you needy demanding people were that way back in the 70's and 80's, too. Only back then you'd get an even bigger earful upon returning home at the end of the day because by then the person would have worked themselves up into a lather over not being able to reach you all day. As if you're supposed to do nothing with your day but sit by the phone waiting to cater to them. My parents and I heard enough petulant answering machine messages over the years, trust me.
If anything, the technology just forces me to lay it out on the table and settle things once and for all. There is no tension and no obligation because I already went over it with these people. I'm very blunt.
Once when I got harangued for not calling back fast enough I said simply, "What, you want to have conversations with me when I'm on the toilet now? I am sorry but I'm not free every minute of the day you know."
If they don't like it, they should not have gotten in my face to begin with. I was a "sweet nice girl" the first 35 years of my life and all it got me was heartburn and migraines and a to-do list of obligations a mile long. GrumpyMom has it so much better. And I have as many friends and loved ones now that I'm a grumpy old sow as I did when I was a sweet young thing. Only now nobody thinks they can push me around. They know better.
My "friend" is an exception only because clearly she is not mentally healthy. I'm not qualified to diagnose her but from my seat here in the peanut gallery she appears to have narcissism mixed with massive insecurity that manifests in massive melodrama. So I can not have a reasoned, logical discussion with her about it. It's impossible, I've tried. She gets insecure and accuses me and my family of hating her or her lovely children. It's ugly. I know if there were no phones, she would just simply show up at my door. I did have a similarly crazy neighbor once who did that. The only solution we had after repeated talks with that lady was to move!
So at some point either she will jettison me from her life or I will jettison her. It will be a shame for our children, who are good friends. Her children, though, are beginning to mimic her obsessive need to have what they want when they want it. One of her children now no longer accepts leaving voicemail messages and will dial and redial all the phone numbers they have for us until I intervene and tell her we are indeed too busy to accept her call right now. She is polite and apologizes for disturbing us. It's a bit odd. Perhaps her mother is egging her on. I don't know.
Parseckadet hits the nail on the head. The technology isn't creating the urgency to respond. That comes from within. And with conscious effort, it can be managed. People want what they want when they want it. They will become spoiled and demanding. It's up to you to set your limits and defend them. You shouldn't give up the Apple Watch unless you want to because it's an utter dud for you. It does so much more than push notifications, after all.