Because they didn't know they had an appointment. True story.

Also ts bodoh everything also feel the need to spin into fud.

Like I said true story. It happened to my relatives.

Sure you can put forward your assumption if you have a good enough sample size and a reasonable hypothesis to go with it.

I have multiple elderly folks who don't go out much so will not open their mysj and there was no other notification. Heck even I won't open the vaccination page for no reason. Some missed their appts and a few got alerted by those who missed theirs and caught it just in time .