On my iPhone 13 Pro, calendar notifications will fail, and the alarm clock will fail to ring. No idea why. I need to reboot my iPhone once a week to fix this issue, and it's been this way since I bought this phone a few years ago. No iOS updates has ever fixed this.
I also have issues with the sluggish interface. Some of my third-party email apps takes several seconds to just load the list of messages. They take milliseconds to load on a Pixel.
My lock screen can sometimes take a bit more than a second to unlock.
The browser dropdown will occasionally load the wrong page when I touch the URL.
The keyboard is more wrong than right, most of the time. Out of all the bugs and problems that make the iPhone almost unusable, it would be the terrible, auto-incorrect keyboard.
The analogy that comes to mind is when the auto industry consolidated to just three large players. Quality was never great to begin with, but it steeply declined after that. It took foreign companies to add real competition to the market.
Apple has been in decline for years now, especially since their only other competitors are Samsung and Google.