No, I'm usually the last person to board. Departure (but not arrival) frequently gets pushed back by 10-20 minutes, though I am making it on time even if not. I have literally never waited at a security check and it takes a minute or two to get through - speaking about EU flights.
90% yes. I don't live nor work in the major hubs, sometimes I fly through as a stopover though (in EU you don't need to go through security again). I do this on purpose - often there are several airports about the same distance from my destination, so I just pick the least used one.
