My Thoughts (I realize this may not have been directed at me):
I am an old man (40) - I can't stand the amount of interruptions the Watch is set up to annoy me with - with the default out of box settings. My iPhone has been on silent since my first Apple Watch 3. I have a favorites list for my spouse, boss, and other folk (about 20) who can call me in any focus mode (sleep/DND/etc). I have most app notifications off because I do not want my life to be interrupted while I'm enjoying my day - it stresses me out. (I don't do this for battery life). (iMessage and most app notifications are turned off for quality of life reasons).
I have Always On Display off because I find when I talk to people it makes them look at my watch and I find it distracting to me when I see my watch too - so I've always had this off (not for battery life purposes). lol.
I have Hey Siri off because I end up accidentally activating it at the worst times (usually while driving). I use Siri quite often to set timers while cooking and alarms for work (I press the button to do this).
Noise Alerts is off because I put my arm out my window while I drive and it kept annoying me that I was in a loud environment. Handwashing is off because if I washed my hands for as long as it wanted to every time I washed my hands, I'd have no skin on my hands.
I love my watch - I use it to unlock my Mac and dismiss the Administrator prompt all the time, I use it to open my trunk on my car - and see my car's charge, it is my alarm to wake up, my voice memo tool, I get 5 day weather instantly when looking at it (Carrot Weather) (rise to wake is on), I use it as a flashlight to go pee at night, I absolutely LOVE the health data - I look at that every day - heart rate, sleep disruptions, VO2 Max, etc. I use it to listen to music while I jog so I don't have to take my phone - all the while being available to take calls with AirPods. I use it to pay at grocery stores, to start charging at some EV chargers. Love its integration with Apple Fitness workouts on TV.
So - from my perspective, I'm not doing any of this for battery reasons. Personal preferences.