A lot depends on where you ride, how long, if other people are with you or if there are cyclists riding nearby.

Some roads and conditions (goat heads for example) cause lots more flats. Country roads with not much around is another reason for extra things like tubes. If you ride in a group, you may not need as much.

I ride along some busy roads, some with little or no shoulders. When I flat, I want to get going as quick as possible do I always have a spare tube and CO2.

I carry a mini pump in my jersey pocket and a pack with levers, spare tube, CO2, and patches. But I am usually near other riders in case something major happens. I also have a phone.

Other than occassional flats, I haven't had anything else happen in over 20 years of riding.